A jumper offers a supported, elevated seat for baby where he or she can touch the floor with his or her feet and push off the ground in a jumping motion. Doorway jumpers require being attached to a doorway for support. Some jumpers also include a tray with toys and activities.
We like this one – new or used is fine.

Graco Bumper Jumper,

http://www.amazon.com/Graco-Bumper-Jumper-Little-Jungle/dp/B000WJLKQM?ie=UTF8&colid=AVTM54ZTN92S&coliid=I36WVOJP2G78EQ&redirect=true&ref_=br_it_dp_o_nS_ttl&vs=1