As long as you declare them as personal property and not used for commercial gain, its very easy to cross--although you will get some odd looks

Also, be prepared to show a receipt--doesn't have to be the actual receipt just a receipt declaring what it is, condition (hint non working) and price paid. If you are over for more than a day you are allowed up to 300 (or 500) in purchases as long as its not booze or smokes.
On an aside, if you are crossing at detroit go for the tunnel (less traffic) or cross at port huron--also less traffic.
I live in canada and work in detroit so I've crossed more than a couple of times. As an american you'll have more trouble getting into canada empty than getting into the us loaded. The opposite is also true--I used to live in chicago and those illinois plates breezed us through customs one way but not going into canada--"any weapons to declare, any drugs, no radar detector, did we mention guns yet?" Kind of funny actually
