No not an actually cat emulator 🙂 it stands for Classic Arcade Emulator it seems that site i mentioned a few days ago has got there own DEVKIT and started on there emulator. Its not been realsed yet but looks promising the bad news is u will need a thing called DCXfer to make it work 🙁 here is a quote from the site:

Coming Soon – The DC version of the CAT emulator – Classic Arcade Trip…
(Requires DCXfer or DCXferPro to work)
Written in 100% SH4 & ARM assembly language!!!

For more infomation click here and goto the DC page.