According to their website:
To be eligible, products must be in working condition and must not weigh more than 5 lbs. Eligible products include mobile phones, MP3 players, gaming systems/games, GPS receivers, digital cameras/camcorders/lenses, headphones, tablets/e-readers, laptops, digital fitness, digital streaming boxes, radios, recorders, radar detectors, scanners, portable hard drives, wireless routers and Bluetooth speakers/headsets. Batteries, home television sets and non-working electronics do not qualify.
Some of the items listed are worth far more than $5, in my opinion. The website states that $5 is the "minimum", but it does not state a "maximum" value, at least I couldn't find it.