My buddy and I were swapping webcomics the other day and he got me hooked on a few more.
Memoria is a relatively young comic with only 99 pages so far, but shows some great promised, especially if you like the Mother\Earthbound series of games (specifically Mother 3). It takes place after the events of Mother 3 and might have some spoilers, so if you have any interest in that game (by the way, play that game) do so before reading, but it doesn't seem as if you'll need to have played or know about the game to enjoy the comic.
TwoKinds is about a... lot of stuff. It has a really interesting and fairly complex story that's presented in about the clearest way it can be and is fleshed out by an incredibly well written cast of characters. Unfortunately, the author is only able to update once a week at best and it's pretty hard to wait for updates, but when they come it's like Christmas. It gets fairly sexual at times but is never explicit or NSFW.
Here's a list of one-off comic strips that I also like to have to round out my days:
VG Cats: Video game and cat humor. Updates "Mondays," though recently it's been monthly at best.
The System: Work humor. All art uses various symbols from signs. Updates at least weekly.
Brawl in the Family: Videogame humor, mostly Nintendo. Updates Tuesday and Thursday (I think).
XKCD: Geek humor, mostly about math, science, or coding. Can get NSFW. MWF updates
Cyanide and Happiness: Adult and off-the-wall humor. It's almost always NSFW. Daily updates.
Gunshow comic: "Child-Trapped-in-an-Adult's-body" humor. It gets pretty weird and hilarious (and NSFW). Updates are on hiatus.
Dueling Analogs: Gaming humor. Can get somewhat NSFW, but normally keeps it more or less clean. Updates at least once a week.