You might just get away with 20 dollar cheapos at the drugstore.
If you're lucky.
I know I get away with them. I use them for close viewfinder work on camera and that's about it. I keep a pair of my single vision glasses in the car for driving and another identical pair in the bedroom for watching TV. For the computer I don't need anything, but of course I have 3 very large monitors and a 42 inch TV set for evaluation use.
But I didn't need anything even when I was using 24's.

"The Best of the Leon Russell Festivals" DVD
deepfreezefilms.com