I’m playing ICRPG on and off for 7 years now, I think, and while we enjoy other games and systems for shorter or longer campaigns and one shots, I always come back to ICRPG when I want freedom and quick game play.
But it is more than that. Somehow ICRPG made me start drawing stuff by using index cards. It told me not to worry about my level of skill when it comes to drawing and now I can visualise rough concepts with the help of a few sharpie strokes. The artwork of the book is simply inspiring and also taught me a lot on how to get reasonable results.
ICRPG also taught me to not worry so much about the rules and feeling free about coming up and trying out my own ideas. The Master Edition is an excellent example on how easy it is to modify the game and how complex and detailed it can actually become, if done well.
Relics of Odium adds another level on that, telling me a different concept - it is the items you accumulate that separate the characters, not their abilities. Which adds a nice touch and differentiates the system from a lot of games out there.
Also, the community - I love this forum and the ideas, the communication and discussions here. Simply something that I can enjoy big time 
Let’s not forget the Runehammer videos … so much fun to watch and great advice, ideas and general information …
Thank you all!