On a whim, ordered
the MyKee tool by KoyganiAt approximately 56mm by 28mm (measured with a ruler), it's on the large size for a key. Quite light due to the titanium construction.
It boosts a number of tools as listed on the back of the business card that came with it
The blade was a little disappointing. DULL. You can see where I tried to draw it across that business card numerous times along the right side to test the blade. With the deepest cuts, I was applying pressure and it was tearing in, not cutting. Since it didn't come with any kind of cover for the blade, I guess it would be impractical to make it sharp if one carries in a keychain. Well, unless you don't mind reaching in your pocket and slicing your finger occasionally.
Given it was $19.99 shipped for the brushed finish version (other models were $5 more), could be good for someone's OPT collection. But I wouldn't carry it on my keychain.