Toshi - A browser for the Ethereum network
Bitcoin Wallet API - New API with proof-of-concept Chrome extension
MyEtherWallet - MyEtherWallet is a free, open-source, client-side interface.
SpectroCoin - Bitcoin debit card and wallet
Exodus.io - All-in-one app to secure, manage and exchange blockchain assets.
The Bitcoin Design Guide - Open source handbook of bitcoin product best practices