well, right now I'm listening to a lot of:
Nine Inch Nails - the Fragile CD is amazing. Dark. Thoughtful. Industrial....Give Reptile, the Frail, Where is Everyone?, Gapital G and The Hand that Feeds a listen
Tool - lots of their stuff is great, great lyrics. Give Lateralus a listen that and Aenima
Red Hot Chili Peppers (always a staple on my iPod)
Coldplay - the Scientist is my fave song from them
Elton John - I have his Greatest Hits CD in my car at all times. I Guess Thats Why They Call It The Blues is my fave song of all times.
Blue October - I love almost all of their stuff. Maybe it's an aquired taste, cause some people don't like their 'sound' but I do. Give Black Orchid, Congratulations, Into the Ocean and Calling You a listen.
The Beatles (they will always be awesome!) - all of their stuff is amazing to me. Too many good songs to list. I would say get all of their CDs and find your personal fave.
David Bowie - listen to I'm Afraid of Americans. It's a nice mix of Bowie and NIN. Also: Ziggy Stardust is awesome.
Queen is FAB! I have their greatest hits collection and I take it on long road trips.
Vanessa Carlton
The Yeah Yeah Yeahs - Gold Lion and Maps are good songs
Sufjan Stevens
The Decembrists
One Republic
Death Cab For Cutie and
The Postal Service - same singer, similar vibe
Mazzy Star - I <333 Into Dust
Jason Mraz (especially his new album)
Our Lady Peace - especially Boy and Starseed
Regina Spektor - Fidelity, Poor Little Rich Boy, Love Affair, That Time <333 and Samson are my fave songs by her
and
I wish I could send you the "My Favorites" list off iTunes.