I see Ethererum as somewhat similar to a VC firm. You buy Ether and invest them in ICO or IEO by trading the Ether with the ERC-20 tokens offered by the project. The projects get paid in your ETH that they can later convert to Fiat or use as is for development and marketing activities.

Check out Farm2Kitchen (F2K) Token for an example, which is a token on the Ethereum platform and is used for crowd-funding using IEO which is currently ongoing on ProBit.