I found scotch permanent mounting tape rolls at my Target store for 3.14 each (1/2 inch, 2.08 yards).
There's a peelie coupon on the rolls for $1 off, and there are some $2 Scotch mailer coupons floating around off a Scotch purchase. I had two coupons (thank you, random coupon leaver) and so I scored two rolls for 14 cents EACH!
Even at 2.14 a roll, it's a good deal, and you can cut the tape down to size.
FYI!!!