You might give the Nikon 5400 5MP (5/28/03) a try, ~$150
or its replacement the 8MP 8400 (9/16/04), ~$550
or the 12MP 5100 (8/30/07), ~$282.
Depends on what you typically take pictures of when you carry your camera on your bike. The cameras I listed, the lens lies more in the wide angle spectrum than the 5700.... better for bike shots without having to back so far away from the subject... worse at being able to zoom in on landscape shots etc...
They are more of a rangefinder size camera in the 35mm world, compared to the semi-SLR size of the 5700.
But personally I find the 5700 small and light....
but then I normally travel the airports with a 50lb backpack as my carry on,
and if I ride my bike somewhere I need to lock it up, I ride with a 12lbs of log chain across my shoulders...
YMMV