I love value blades; it's actually amazing when you look at just how much you can get for so little.
Buck Revel - Great little gem in Buck's lineup, the spine flipper/button lock combo makes it good for anyone worried about accidental deployment, and is actually really fun to play with. Useful choil, too.
Byrd Meadowlark - Cheap, compact Spyderco design. Any questions? No? Good.
Cold Steel Tuff Lite - The most utilitarian blade Cold Steel has ever made, and actually very, very useful.
CRKT Drifter - Small, basic knife, with a G10 linerlock and SS framelock model. Everything you need, nothing you don't.
Kershaw Chill - Personal favorite budget Kershaw. It's a sub-20 dollar, 3" blade that flips incredibly and weighs under 2 ounces.
Kershaw Zing SS - Basically a sexier Cryo in my eyes. It's lighter, slimmer, got a longer blade, and can be de-assisted.
Ontario Rat I or II - Pick your length and go nuts.
SAK of your choice - It's a SAK.
Schrade Mini Drop Point - The thumbstuds snag on the pocket a lot, but a small, relatively light framelock that comes with a surprisingly good steel (9Cr18MoV) for the price (about 12 dollars)
Sanremu 710 - Say what you want about it being a "clone," this is a great blade for 12 dollars.