Hi, Yeoman Droid, I've been looking for the same thing - how to control one Android device from another. I've just come across Limitless Remote which looks as if it might be the thing I've been looking for. It certainly works for my Android phone controlling my Windows XP PC wirelessly (they are on the same LAN). I'm just waiting for my wife to finish with our tablet to check out Android to Android.
I've now installed Limitless Remote Service on my tablet and my phone running Limitless Remote works fine as a mouse, keybord, media controller, voice to text input etc. I'm doing it wirelessly with them both on the same LAN but it claims to support Bluetooth as well. The only disadvantage for some will be that the tablet (i.e. the controlled device) has to be rooted for it to work.