This is something that I want to plug for a couple of reasons. First, it is going to be a kick-ass book. Finally, with Fourth Edition, GURPS is able to handle super-powered characters. Second, I get my first GURPS Playtest credit in this (check the Table of Contents preview) which is pretty darn cool for me.
My first "professional" attempt at becoming a game designer was back in 1986. After seeing a "want list" for proposals (back in Roleplayer, the zine for GURPS that SJG originally published) for the first edition of GURPS Supers, I sent in a proposal. It was awful and, rightly so, I received a rejection letter about it. It was a personal rejection from Steve Jackson though, which I actually thought was pretty cool.
If you haven't yet, you really need to check out GURPS 4e, it is the best version of the system to date.
GURPS Powers
"Save the World . . . or Destroy It!
"GURPS Powers is the ultimate book for the ultimate characters in the new Fourth Edition of GURPS! Here's everything you need to create every kind of amazing, off-the-chart superhero you can imagine . . . as well as amazing wizards, wuxia fighters, shamans who command spirits . . . even gods!
"Written by GURPS Line Editor and Fourth Edition co-author Sean Punch, GURPS Powers introduces some new rules, but it is mostly about using the rules that are already in the GURPS Basic Set to cover superpowered characters, megawizards, and earth-shattering psionics. GURPS Powers also include guidelines for 'special effects' and several different ways to vary a power on the fly -- two crucial concepts for comic-book superheroics.
"GURPS Powers is a Fourth Edition GURPS book that completely replaces the Third Edition books GURPS Supers and GURPS Psionics. Like our other Fourth Edition supplements, it's a gorgeous 240-page, full-color hardback.
"If you've got a high-powered campaign . or high-powered players . you want GURPS Powers!"