Madmax has been a staple in this community since the early days and she's still going strong even today. While she is still known for her comics, she also started a couple tumblrs some time back filled with the same kind of zaniness we have come to expect from her work.
One of those tumblrs is Madmax's Silly Comic Shop. The idea behind the tumblr is that you pitch a small idea to the tumblr and Madmax might respond with a comic to go along with that idea (sometimes in an unexpected fashion).
The tumblr can be a bit mature at times so just fair warning in case there are those of you out there that would rather avoid that sort of thing. You can start at the first page here or visit the front page here.
Finally, if any of you have any ideas for future Tumblr Spotlights, send me some suggestions at firstname.lastname@example.org. We don't know all the tumblrs that are out there so I'm sure we are unaware of some real gems.