OK Steve, true, but I was just speaking generally. I guess I should have added this:
I DO THROW IT INTO THE POST OFFICE COLLECTION BOX all the time, and never had a problem, if:
¶ it is under 13 or 16 ounces (I always forget which) and
¶ is under a certain fairly high amount (it varies), and
¶ has postal form 2976 (the short customs form).

I was told this by one clerk at the post office, and he was proven correct. I have sent chips this way all the time and never had a problem. I continue to use the old green forms with the white attachment. I leave the white attachment part on, and throw the entire thing into the collection box. You can do this with the new all-white forms too.

Here is a neat post office "Customs Form Indicator:"
http://ircalc.usps.com/CustomsFormsCalculator.aspx

Incidentally, if it is a very slight parcel with just one or two chips, I don't think you even need the customs form. I never had a problem, but now-a-days I always attach the customs form.

Robert