The Byrd brand of knives offers some pretty good value for the money. Any of their knives can be found for under $25 on the internet.

I have a Kershaw Vapor ($20 at Walmart) that I recently started carrying. It is pretty comfortable to use. I don't know how it will hold up in the long run.

I agree with the above poster that the Spyderco Delica is a nice knife, but it looks like it might be a bit out of your price range.