Best portable sharpener?

[tattoosteve99]

What would you recommend for a "combo" blade?

For the serrations maybe a diamond coated round sharpener. A small stone for the flat part. You may even find a dual purpose sharpener that has both.

Something like this would work great!
http://www.sharpeningsupplies.com/Diamond-Card-Sized-Sharpener-P19C24.aspx
Not so much for the serrated parts but it might work

[MeadMaker]

What I had typed was something like:

The 600/1000 stone is old but many woodworkers store their waterstones in water, even their new stones.  Its not really necessary with the finer grits, but on coarser grits it saves time.  If you don't store them in water, you have to soak them before use.