As part of its Labor Day Sale, Overstock offers its Overstock Club O Annual Membership for $4.95. That's $15 off and tied with our July mention as the best Club O discount this year. Overstock Club O gives you unlimited free shipping at Overstock and a 5% reward in Club O Dollars.

Note that this will set to auto-renew, so you'll need to cancel before your year is up in order to avoid subsequent membership fees.