ThredUp is offering a free $15 credit when you use coupon code JUNE15 at checkout. ThredUp has quite a few items priced in the $2-$4 range, so you should be able to get 4-5 items for around $7 to $9 (the cost of shipping).
This offer is valid through June 21, 2013.
Thanks, Freebie Finding Mom!
(Note: Some of the links in this post are my referral links. Read our disclosure policy here.)