I'm sure everyone on my friends list has already heard about it, and probably done it, but just in case you're missing out, may I remind you:

Go watch Dr. Horrible's Sing Along Blog NOW

Or at the very least, as soon as you have 15 minutes to spare. And then another 15, because the second act is up too.

If you're still not sure, let me help you decide.
If you are a fan of:

Joss Whedon
Nathan Fillion
Neil Patrick Harris
Felicia Day
Once More With Feeling
superheroes
musicals
musicals with superheroes
ass kicking
love stories
or
THE INTERNET

you should be watching Dr. Horrible's Sing Along Blog.

It's up, it's short, and it's FREE, right now. But it all comes down at midnight on Sunday. So you need to watch it. NOW.

"That's got to be the stupidest question i've ever heard. I guess I'd row on out into the middle of a lake, bring along a bottle of tequila, my sax and some Bach."