Leatherman has produced quite an astonishing variety of smaller sized multi-tools in the past, and that trend doesn't appear to be abating anytime soon.
Before I start, here are my little Leathermans by the numbers:
Micra - 40
Squirt E4 - 4
Squirt P4 - 8
Squirt S4 - 10
Squirt ES4 - 8
Squirt PS4 - 5
Style - 6
Style PS - 2
Style CS - 6
Total = 81
The Micra is the longest running mulit-tool that Leatherman has in continuous production. I believe it came out in 1996. It is now 2014, which makes the Micra's production run 18 years and counting. Phenomenal when you think the average model life expectancy can be measured in a few years. The Micra just has a great simple design based around a great pair of scissors.
For the collector, there are several interesting variants to the Micra. The Stainless steel Micra is very common. However, the painted Micras of the original form are harder to come by. Especially as the paint tends to fleck off with any form of use, so finding a good example can be a little bit of a chore to downright scarce. The gold Micra is a Texas Toolcrafter custom gold plated job.
Once the coloured original Micras ceased production, they then decided to use a plastic clear overlay on top of the stainless steel Micra. I beleive this was done to make them more durable to wear and tear. Of course this only increased the bulk of the tool, and dirt can find itself between the overlay and the tool making them hard to clean.
Of interest to the collector, are some of the special Micras produced. For example, there is the 2009 America Micra draped in an American flag. Then there is the pink breast cancer Micra that was sold for a short time from limited locations. It is located next to a pink anodized Micra in the following photo. Come to think of it, once the plastic Micras were produced, Leatherman then started to produce coloured Micras with a metal overlay. This didn't show the dirt as much, and looked a lot better than the plastic covered ones. However, as with the plastic covered Micras, fetching the tweezers is not as convenient as the original design.
Then there is also the relatively rare sports Micras such as the Portland Blazers Brandon Roy, and the green Portland Timbers. Also direct from the Leatherman Factory store, is this rare green/black swirl Micra. I am not sure if this was an error, or an experiment.
Following the successful Micra was the Squirt family introduced in 2002. Some of these are still in production, while some are now discontinued. The original Squirt series consisted of the E4, P4, and S4. All of these are now discontinued. They featured beautiful anodized aluminium scales and very much resemble mini Juices. The E4 features an electricians wire stripper head. The P4 featured pliers, and the S4 was supposed to be the successor of the micra with its scissors. We now know it failed in that regard as the Micra is still going strong.
These tools came in a variety of colours, mostly gray, red, blue, and pink. Of interest to collectors, one of the pink Squirt has "lady" written on it.
For the collector, there are some interesting models here as well. During the original Squirt's run, there were several errors made at the factory. The nice thing about Leatherman, instead of destroying their mistakes, they will often sell them at their factory store in Oregon. There were several errors made when they introduced their Knifeless Squirt which is a fairly rare model these days. I guess some factory workers mislabeled a few and re-ran them through the printer to X the "knifeless" out as they had the blade in them. On top of that, there were a few errors in assembly as well. In the next photo, you can see a Knifeless Squirt along with two errors, one featuring a nail file, the other, a metal file. Also in this photo are two red S4's mislabeled PS4. I can only assume this must have been towards the end of the Squirt S4's run when the newer PS4's were being introduced.
Also of collector interest, are some advertisers for Make: magazine. What makes these interesting are the cute sayings on them. In the next photo, you can see 2 Squire E4's with different fonts for "Warranty Voider."
After Leatherman produced their Squirt E4, P4, and S4 family, they extended it with two models that replaced the older 3 models. The Squirt PS4 and ES4 were introduced in 2010. Following Leathermans standard annotation, the PS4 features pliers with scissors, and the ES4 features wire strippers and scissors. Now what makes these interesting to collectors, the original run features rivets on the handles. The second to present run feature little torque bolts instead of the original run's rivets. On top of these changes, the PS4 and ES4 both featured a new textured handles in comparison to the smooth handles of the older Squirt family.
In the following photo, if you look closely at the upper 3 Squirts, they feature the original run's rivets. All others on the bottom two rows feature the newer retention system. In this photograph on the lower right hand side, are the Leatherman Styles. These are leatherman's smallest pocket based multi-tools. They were introduced at around the same time. There is a special run for breast cancer, which I believe would be of interest to collectors.
Much like the older Squirt family, there were several special run advertisers for Make: magazine. Once again, they feature cute slogans. Note that the two loser Squirts feature the original run's rivets, whilst the other two are newer.
Meanwhile, Leatherman took a different turn from the Squirt lineup. These different tools they called Style as seen in the above photograph. However, there would be two more additions to the Style lineup, the Style PS, and the Style CS. The Style CS came out in 2010. The Style PS came out the following year in 2011. Following Leatherman's nomenclature, the CS features scissors coupled with a knife blade. The PS is plier based, but instead of a knife, it features a smaller pair of fold away scissors. The PS was produced to meet flight requirements, hence the lack of a knife blade. The Style CS and PS are basically cute mini Skeletools.
For collectors, the Style PS is rather bland with little to no variations that I am currently aware of, However, Leatherman saw fit to produce the Style CS in a variety of colours. With that said, Multitool.org made a special limited run of each Style. I would imagine these might be very attractive to the collector out there. In the following photo, these special MT.O runs are presented in their metal presentation boxes in the background.
Who knows what the future will hold in regard to Leatherman's smaller multi-tools. In the past few years, Leatherman has embarked on an offshoot of pocket tools that are specialized towards sports. To date, they have produces 13 different non traditional for Leatherman tools. Here is a photo of these. I do not include them as they aren't folding tool based multi-tools. I have to wonder how many more of these types of tools Leatherman is going to produce, and just how successful these are in the market place.