You can disable password recovery...
router(config)#no service password-recovery
But, there are ways around that.
If you have a SmartNet contract on the router, you can prove where the router belongs, but that's about it. If anyone ever tries and gets smartnet coverage on the stolen router (esp. the high end devices), then Cisco would know (they check serial #'s) and the thief would likely be caught (paper trail)---if a thief steals a 12000 and resells it, the chances that the buyer would get smartnet is nearly 100%.
Also, the 2610 and 2900 switch (if it is a 2912/24XL) are both more like $50-$75
/
tim@tim-laptop ~ $ sudo apt-get install windows
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Couldn't find package windows...Thank Goodness!