Don’t have much experience with them but if I needed one I would probably go for something like this at $30.00 but I like canvas and non-flashy color schemes..

You asked about messenger bags a month or so ago; I’ll stick with what I said then: check out “timbuk2”: http://www.timbuk2.com/

While Timbuk2 has a lot of higher priced items, they do have bags under $50, and they are a reputable brand.

I bought this one in 2001 and still use it daily. Sadly REI no longer makes them so that is a link to eBay.

http://i.imgur.com/MHZnotw.jpg

It is a great bag. I’m tempted to buy the one on eBay. I originally paid 90 for mine.

They are a bit above your price range – but maybe you can find a used one on E-Bay.
I buy my work messenger and backpacks exclusively from this place because they last for years and years and years..and look great (not worn) and I use them daily and in tough travel conditions.