First a little background, every season brands are left with leftover articles from that season that (obviously) cant sell, in part because offering a luxury product at a discount every season hurts brand image, so they pass them off to sample sale sites which sell the goods for them at highly discounted prices "on the low" so to speak, all sites are 1000% legit and Gilt had a feature in Forbes (http://www.forbes.com/forbes/2008/0225/070.html). Some of the sites I believe you can sign up for by yourself or get put on a waiting list to sign up while others are strictly by invitation only.
Gilt Group - Probably the highest end sample saler, has stocked Y3, Gant, Richard Chai, RL Purple Label, John Varvatos, Common Projects; mostly high-end designer labels at very highly reduced prices
(Invite: http://www.gilt.com/invite/gilded)
MyHabit - Luxury sample sale site backed by eCommerce titan Amazon.com, nice selection of high-end labels (Armani, Rick Owens, Damir Doma, DRKSHDW, Prada, you get the idea =p) for VERY discounted prices.
(Invite: http://myhabit.com/ref=qd_mr_per_l?refcust=ZOJBCELVLRBZWG3MTM2QTATLTU)
Belle & Clive - Another designer sample sale site, still in its Beta stages, started by luxury retailer BlueFly; stocks high-end designer goods; Prada, Ferragamo, Hermes, YSL, Zegna, Y3, Gucci, etc. etc.
(Invite: http://www.belleandclive.com/invite/35cbb1drf?partner=friend)
Hautelook - Sample sale site somewhere in between high-end and streetwear.
(Invite: http://www.hautelook.com/invite/KPerez125?sid=99992)
PLNDR - Strictly streetwear sample site, owned by Karmaloop, stocks BLVCK SCVLE, Play Cloths, BBC, etc etc.
(Invite: http://www.plndr.com/plndr/MembersOnly/login.aspx?r=1277630)
JackThreads - Another streetwear reatailer; owned by the Thrillist group. Similar offerings to PLNDR in that it mostly deals with streetwear brands.
(Invite: http://www.jackthreads.com/invite/vessaint)
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