I've been hearing about the 'MapMyRide' website for a while now, but only just got around to checking it out. Say you're looking for someplace new to ride your bike to. You can log onto the site and check out rides other people have taken and mapped. They tell you about the scenery, the distance, the difficulty of the ride, etc. and provide a map.
Or maybe you want to be a little more original. MapMyRide also lets you plot your own bike rides over mountains (view elevation), through the woods (topo maps), and through the city (street level views). And once your cycling map is complete you can view it in 3D, satellite form, or share it with friends.
There are lots of other options on the site as well. Here's a link to MayMyRide. Now I just have to get the Huffy out of the garage and tuned up.