Don't know about "floating", but right now Microsoft is giving away free downloads of a great little calculator app called 1-Calc Lite. I think this is the link:
http://www.microsoft.com/windowsmobi...lications.mspx
Has a pretty cool conversion feature and everything. While you're there you can nab your own free copy of Space Invaders, for a little retro gaming action. Hope this helps.
~KC