*doesn't keep up with music too well*

Hot Water Music
Post-hardcore from Gainesville, Florida, these guys can take a bit of getting used to, since their music can come off as somewhat reserved, but I just really love these guys.
Picks: Bleeder (Cover of an Alkaline Trio song, from a split EP they did together), Wayfarer (The Punk-O-Rama 7 version)

The Weakerthans
I've not listened to a lot of their stuff, but every one I have I've loved.
Picks: Plea from a Cat Called Virtue

YUI
A relatively new J-Pop artist, she's actually really quite good. Focusing on her guitar playing and vocals, her work comes across as quite subdued compared to the typical frenetics of most J-Pop artists, and it's really quite refreshing because of it.
Picks: Blue Wind, Just my way, Rolling star

HORSE the Band
In some ways, I guess they're kind of similar to Machinae Supremacy in that they use synthesisers to recreate NES sounds in their music, but they don't do many songs about game characters. What they are though is hilarious. The vocals are rough and far from the greatest, but the music is excellent and they're a lot of fun to listen to.
Picks: A Rusty Glove, Birdo, Bunnies, Cutsman

Jecano
A very small band based in England, Jecano are utterly rocking. Awesome vocals and fat guitar riffs dominate their music, and they're pretty awesome live too. I just wish they'd get their first album out already. All of the songs from their first three releases are available to download from their site, http://www.jecanorock.com/
Picks: Hilltop Hanging, Tyrewall, Ultimate Jedi Death Move

ORIGA
Russian singer, based in Japan, I honestly think she's the best vocalist around today. She's garnered recent attention for singing the opening themes for all of the Ghost in the Shell: Stand Alone Complex series (GitS:SAC, 2nd GIG and SSS), but has been recording for well over a decade now.
Picks: Tersicore, There Must Be an Angel, 我が心のマリア (Maria)