Usability News – Does exactly what it says on the tin.
UX Mag – Informative articles for eager-to-learn usability folks.
Jakob Neilsen – The controversial granddaddy of usability still informs and inspires.
Smashing Magazine – UX Design is an ezine for professional UX-minded web designers everywhere.
Don’t Make Me Think by Steve Krug is still the best introduction for usability beginners, and a regular re-read for the converted.
Task-Centred Design — possibly the best five bucks you’ll ever spend.
Karaoke Capitalism, and its predecessor, Funky Business are excellent guides to business in the 21st Century.
Design Comics is a great resource for creating storyboards if you don’t have graphic design skills.
Balsamiq Mockups is an excellent wireframing tool that never lets us down. We use other tools like Axure and Photoshop, of course, but Balsamiq’s what we use most.