Most computers from $20 to about $100 have similar functions.
Here's a good one on sale for $17.99
http://www.performancebike.com/shop/...tegory_ID=4110
It's wireless. No cadance, just the wireless speed sensor, so no wires.
Or wireless speed and cadance $99
http://www.performancebike.com/shop/...egory_ID=4110#
Or wireless speed and cadance in 1 computer, $150
http://www.performancebike.com/shop/...tegory_ID=4110