If you’ve never heard about it, 24 Hour Comics Day was invented by Scott McCloud and challenges cartoonists to draw 1 comic page per hour, thus completing a 24 page comic in 24 straight hours (or two 12-hour stretches for a more reasonable variation on the challenge). AND IT’S THIS SATURDAY!!! On their site you can read up on the event, download “survival kits”, and even look for events in your area!
I tried this once, 3 years ago now, and it was fun, a bit stressful, but ultimately rewarding. Definitely a good way to jumpstart your art-making! I only managed 16 straight pages, but finished it up later, and you can read it all here (on my DeviantArt, which is pretty out of date).