The criteria for this list is how unique and revolutionary said anime are and how much I recommend them. Keep in mind that the order of this list isn't based on how much I like them.
All the anime I own
This list only includes TV anime and OVAs, and the #1 entry covers both Ashita no Joe series.
Should I watch this anime? Shouldn't I? These are the anime I just can't make up my mind on! (For most of them, I'm actually either just waiting for someone to recommend them to me or waiting to see...