You may not be able to get ICS and all of its brilliant features yet, but you can still rock out with the "look and feel" of the new OS. A sharp modder, Sonnysekhon, over at XDA has created a custom ICS theme for use with the same Theme Chooser app that is in CM7. The installation is simple; just download and install like any other 3rd party app, then use Theme Chooser to apply the theme. Here's a download link below, and you can hit the source link for more details.
Download: ICS_Custom_Theme_Alpha
Source: XDA