Bike alarm?

[DucatiTorrey]

Has anybody installed an alarm on their bike? If so, what brand, did you do it by yourself, and has it helped deter any thefts yet? Are they worth it?

Thanks

[TobyDanger]

Just posted here:

http://ducatimonsterforum.org/index.php?topic=18485.0

Did it myself, took maybe an unhurried hour...  Dunno about deterred thefts.  My perimeter alarm has been tripped a few times and my motion once.  Big piece of mind at home or out and about.