I'm gonna jump in on the EOS-3 bandwagon...I rented one a long time ago (when all I had was a Rebel G), and loved it. Bought a used one for myself not long thereafter. I recently got a great deal on a 1V with the EOS Link software and adapter, so I'm now selling the EOS 3 here on APUG (shameless plug).
If you absolutely have to stay below $100, or are looking for something a little lighter weight, go with the Elan 7N, it's probably the best choice (and the newest). AF and metering similar to what you might have on the digital side (depending on your camera). Don't mess with the film Rebels, IMO. (Though I'm perfectly happy with my digital rebel.)