Cheap Pocket Knife

Klein--hard to beat the quality for the money. Find them at hardware stores and electrical supply houses--that's Klein's niche market. Among those that really use 'em, are hard to beat.
The Harsey Air Ranger by Gerber, the Benchmade Mini-Pika, you can probably find either for around 20 - 30 bucks and will serve you well.
Buy a real cheap knife for $10.00 and save the other $30. till it's a hundered then ask again. I just told my Nephew that and he bought some Buck Clone at Tractor Supply for $10.99 and know is saving for a Kershaw "Bump"
You might be able to find a cheap Buck on eBay. A real workhorse that you may find carrying more than any better knives you may buy, depending on the uses you would need a knife for.
I would go with a Boker Magnum, or a kershaw storm II. There both very well made knives for the price. Bokers can be had for around 25 or so and the Kershaw storm II around 29 or so. Hope it helped :)
A good knife that I like is the Gerber Gator II (about $30 at Wal-mart)- although it is pretty large, but I like it because it fits my hands. It is a lockback style knife (that took some getting used to for me). Most Gerbers, Bucks, Old Henrys, or Cases (and other brands) in this price range are good everyday cutters. Not fancy or refined, but work well. Another thing that might work is one of those folders that uses a utility knife blade- just replace the blade when it dulls. Benchmade's Red class knives fit your budget, too.
Some decent choices for small, traditionally styled knives are the Rough Riders... about 8-10 shipped on eBay. Some nice ones include the trapper, sodbuster linerlock, and "one-arm jack" or razor 2-blade trapper.
Probably 440A steel. Fit and finish probably is comparable to Queen or Case, hey snap open fine, come decently sharp, and won't hurt the wallet. The Steel Warrior line seems to get good reviews as well.

Douk Douk and Mercator K-55 are other choices as well.

For more modern styling, I'd agree with the recommendation of Byrd line of knives.. the Camillus EDC is a nice one too, though the lack of choil is a bit odd for me - makes closing it a more precarious affair compared to a Delica/Subcom F. Also consider the Kershaw Storm I and II.
I'd order a Cara Cara from Byrd. If you'd rather not order online, take a look at Victorinox, Buck and Kershaw knives at Walmart, Target and the like.
Depends on what you want in a knife.

I agree with knifestuff on the Kleins. Top quality, awesome fit and finish, good hard users that really hold an edge well. Steel handles, lockbacks, no pocket clips. Klein is the name in electrical tools. They know good steel. Mid $20s to mid $30s depending on blade length.

Found some places on the web that sell Junglee Marshalls for low to mid $30's. Pocket clip, 3.5" AUS10 clip blade. FRN handle is not as robust as it might be. But the ballance and ergos are good and the blades are awesome.

Kabar Dozier 3" AUS8 lockback with pocket clip ~$20. Don't have one. Just heard good things about it.
Camillus CUDA EDC

(or you can get Spyderco Delica/Endura for about $45.)
I also agree with Knarfeng. I have a KaBar Dozier Folding Hunter with the Aus8 blade. It gets scary sharp very easily and holds the edge well. for $20
I also agree with Knarfeng. I have a KaBar Dozier Folding Hunter with the Aus8 blade. It gets scary sharp very easily and holds the edge well. for $20

I agree. I have cut myself on mine more than I can tell you. I've dropped it. Cut with it over and over and haven't had to sharpen it yet. Good value for the price. I carry mine everyday.
I would say get a Benchmade Mini-Ambush. I got mine at the store for around 34$.
I'd suggest a Benchmade Vex. I got mine for $37 from the 'Pharmacy' guys. It's got G10 slabs, and a great finish and feel. The blade steel, (whatever it is), takes a sharpening and stays that way. Good deal!