1) This is an awesome video of Magneto from X-Men singing his own parody of Lady Gaga's Born This Way. I discovered this just after I saw X-Men First Class, which actually wasn't terrible like I thought it was going to be. Anyway, I suspect this version is even better than the original.
2) Mario Kart Love Song is a super cute song that is exactly what it sounds like. Yay for nerdy love,
3) I saw this super cute video on io9.com. A kid decided to recite the Doctor's epic monologue from The Pandorica Opens for his talent show. He just looks adorable in his bowtie and even Steven Moffat can't deny this kid's talent when he tweeted the link and wrote "Oh well - clearly Matt's time is up."
Here's the speech recited by Matt Smith for comparison.
4) Kirby Krackle, my favorite nerd band, has just come out with a new album called Super Powered Love (which I am totally buying at Comic-Con). This is the first single with the same name as the album about a guy worrying about his superhero girlfriend.