I bought the CodeAlarm CA-145 off eBay for a reasonable price, but since I just installed a better, more expensive alarm system, and since the CA-145 is an "expansion pack", not a system by itself, I figured I could hack around with it a bit :)

It came with a nice multi-tone siren, a 2-way remote, and a receiver for the remote, so I figure I can delve into the wild world of PIC microcontrollers by starting off with an interface between the input/output lines of my installed car alarm, a PIC, and the 2-way interface for the remote.

More on this page as it happens :)