I've got quite a few good ones for you guys...well, to me they're good...
1. http://www.twolumps.net (aka The Adventures of Ebenezer and Snooch!) - I love this particular webcomic because it involves two of my favorite things - humor and CATS. :) Go check them out for yourself.
2. http://www.somethingawful.com - This is an awesome place for humor and insanity. You can check out the forums for free, but you have to pay to join (a one time fee, no biggie there) and post. I'm AbnormalAngel over there. General Bullshit is especially awesome.
3. http://www.ebaumsworld.com/cornholio.html - Because you can NEVER, EVER get enough of Beavis and Butthead, especially not enough of THE GREAT CORNHOLIO!
4. http://www.gaarde.org/acronyms/?lookup=A-Z - Internet Acronym Lookup...This has been useful to me in the past...and it has acronyms that I haven't ever used or even heard of before.
5. http://www.notam02.no/~hcholm/altlang/ - Because knowing how to swear in dozens of different languages might become useful someday.
6. http://www.sparknotes.com - Yes, it's SparkNotes. I rely on this site for supplemental information on what I'm studying (which these days is mostly Psychology and English related, but it's still very helpful!
There you have it for my links. That's the best I can do...it may not be 'modern' stuff, but then again I'm 25, and I wasn't really that modern to begin with...Enjoy!