Does anyone sell a laptop theft alarm?

Question

Ok, I'm thinking an interesting alternative (or addition) to physically locking a laptop to a desk would be an alarm - a tamper-resistant box that plugs into USB or Eithernet port and if disconnected, damaged, or tampered with will sound some sort of audible alarm.

I have an idea to make a double-redundant tamper-resistant self-recharging one but before I go crazy with my soldering iron and RadioShack parts I thought I should look for a pre-made one...but I haven't found any on Google searches (or rather I can't find any that are still being sold)

Thoughts? Ideas?

Answer 1

I really dnt kno about any of those  but i kno dat i have lojack for my laptop. . .  

Answer 2

I have heard of those too,

but there is a program called lojack for laptops

Sounds like a sneaker alternative