Just got back from Costco and they were stocking cheap ($15) athletic shirts in the clothing section. It's a 65/35 polyester/coolmax blend, has a 9" zipper, and a zipped central rear pocket. Not quite a cycling jersey, but it could play one on TV.

From my quick ride, the pros are:
Zipped pocket lessens worry about losing anything
Felt great, good length, collar falls great
Very subdued look

The cons:
Zippered pocket makes grabbing something slightly longer (good for rides where you just want to carry ID/Cell/pump, bad for gels and bars)
Not quite enough difference between front length and back length, some front bunching
Zipper is a little short in front (I prefer 12" or better).

All told, for a dirt cheap almost jersey, I feel good about having it, and if you're looking for a shirt to abuse in bad weather or for short training rides, I'd say to give it a look. But for longer rides where I need a little more carrying capacity, I'll stick to my other jerseys.