During the summer months when I hike, bike ride, and work outside in the yard a lot, and even in the fall when I am cutting fire wood I like to carry my David Boye folder because I'm sweating all over the place and want something on me that won't be hurt from all that moisture..
http://www.boyeknives.com/
This is a really great knife for a number of reasons in my opinion.
1) It is one of the easiest knives to sharpen I've ever had and takes a quick biting edge from just about any old sharpening stone.
2) It is so slim and light you don't even know you have it on you but yet the blade is still a very user friendly 3". It also comes in a very cool blue or yellow color.
3) It is completely care free. Sweat, salts, oils, water, and anything else that would be corrosive and damaging to other knives does not affect this knife. You can clean it off in the nearest puddle or stream and shake it dry and then shove it back in your pocket without worry. For that matter you can jump in the water and swim with it all day even if it is salt water and it won't affect it negatively at all either. Drop it in the soapy dish water in the sink? No worries. You don't even have to spend anytime messing with much more than running tap water over it and wiping it off is an option.
Of course you can get all these same benefits from the Spyderco Salt 1 or the bigger Pacific or Atlantic Salt knives using the H1 steel that is also quite corrosive and rust resistant and for less than half the money but the Boye folder is a better edge keeper than the H1 plain edge knives. I have a Salt also for the money it is great and I do carry the Salt but over time I've just come to really appreciate this Boye folder. At $135 ordered from the link above I'm going to use it too. It is a bit over your max limit but I wanted to mention it. If you get one at Shomertec you can save a few bucks.
I do like the bluejean blue color of the handles on my Boye folder though. I've never seen that from any other maker. People seem to like that when they see it and notice that first.
Anyway, that is my picks. But for $100 there are endless choices out there. The Spyderco Native now available from select Wal-Marts is a great offering also. At $40 it is hard to beat for sure.
Good luck.
STR
