Many years ago, (around 1.09) I was browsing a Sonic Fansite and in the fangames section I saw "Sonic Robo Blast 2" It was the only 3D one, so I went to the website, Downloaded it, and WOW.
At first I was pissed when I found out there were only 3 zones, but when Sonic at the end of the game mentioned an Addon section of the website, I had to check it out. I had fun with TONS of maps. A month later I had about 75+ wads in my SRB2 folder.
It wasn't until about a year ago that I learned how to map properly.