I just thought of some more. These aren't daily visits, but whenever I check them out they're always good for a laugh or read.
- XKCD - an online web comic that speaks directly to my heart. If you're a nerd in any way then you'll like this comic. If you're not then there are A LOT of jokes that will seem lame and nerdy.
- Perry Bible Fellowship - another webcomic that isn't bible related at all. This one is pretty hit or miss. Sometimes the comics are pretty hilarious and quite clever, while other ones are just lame. Art is usually well done though.
- Bash.org - another nerdy site that has collections of funny snippets from IRC conversations. The top 100 has some really good ones.
As for YouTube, I really love the Tales of Mere Existence series of short films. They're poignantly hilarious.