For the investment savvy crowd here's something to check out:

PowerShares WilderHill Clean energy Portfolio (PBW) has experienced a 30% up move over the last few months. This portfolio is designed to deliver capital appreciation by investing in companies that focus on renewable energy and technology. This fund is operated by PowerShares Capital Management LLC.
PowerShares

This fund is near an all-time high but put in general terms research might show that the renewable/alternative energy sector is positioned for long-term growth.

My disclaimer: with any investment you risk losing money; the mentioned fund is specialized to limited market segments so the potential risk associated with this investment would be greater than the risk associated with an investment in a more diversified portfolio/fund.