Excellent prototyping intro

I've just come across an excellent article on prototyping at Smashing Magazine. Combining principles with solid examples and an overview of tools available, it's probably the best overview piece I've read.

Balsamiq mock up inspiration from "champions"

Balsamiq is a great mockup tool - it's quick and simple to use. The Balsamiq champions blog is a series of articles by people who have put it to good use. Worth a look if you prototype (or are wondering why you should) - even if you use a tool other than Balsamiq.

Prototyping and UX challenges with agile development

An excellent series of articles by Ritch Macefield in which he discusses challenges faced by agile teams looking to efficiently build user centred design processes into their work and makes the case for more sophisticated prototyping software.

UX Apprentice - a beginner's tutorial

A nice resource from the Basamiq people that takes you through the fundamentals of user experience design quickly and simply.