There is an Investment program running at the Free Ether Wallet.
There are two levels of the program.
Level 1 provides 0.6% daily interest rate when you store at least 500 ETH in your Free Ether Wallet, and Level 2 provides 1.3% daily interest rate when you store at least 2000 ETH in your Free Ether Wallet
The promotion is active until 01/2017.
More details here: Free Ether Wallet.