Excerpt from their site (Cryowallet.com):
"We're confident our wallets are bombproof when it comes to security. So confident, in fact, there's a wallet with 10 (yes ten!) BTC right there inside it for you. If you can break into it, and you tell us how you did it, we'll send you another 10 BTC for your trouble."
They have created a wallet that executes and exists inside only your browser memory. So even though your coins are stored away from centralized servers where (like gox) others can potentially steal them, you dont have to worry about losing your USB drive or other methos of cold storage as you can just 'evoke' your wallet from any other machine. When you log out,its gone again.
Pretty cool