[skinnynerd]

There are plenty of old typewriters lying around. Although you would still have to take precautions like getting rid of it afterwards and make sure it does not make use of polymer tape ribbons (in which case you would have to destroy and discard that as well).

[smacktoward]

Typewriters have signatures too: http://en.wikipedia.org/wiki/Typewriter#Forensic_examination

[tomjen3]

Sure, but the government wouldn't have a database of those anywhere and getting rid of a typewriter isn't likely to get anybody noticed (I cleaned up in the attick the other day, can you believe what I found?).

[skinnynerd]

Good link, thanks.

[rexreed]

Even better, receipt / thermal printers. No ribbon and pretty much untraceable. Lots of them lying around second hand in flea markets and yard sales.