The Magic Lantern firmware is free and includes a bunch of cool new features for your Canon 7D including focus peaking, zebra stripes, magic zoom, spot meter, LiveView customization, image tweaks, and many more.
The firmware has had no reported problems so far and should work just fine on your 7D, but use at your own risk as always. For reference, Magic Lantern did shoot numerous gigs of footage and photos on four different 7D’s and did not experience any problems at the time of writing.
If you’re interested, head over to the link to download the firmware, and just follow the 5 steps on the page!
