Is there an interactive web-based character sheet for Dungeons & Dragons 4E like there is for Gamma World? I'm not looking for a character builder.
The only one I am aware of is the Character Builder. Though you do have to be a Dungeons and Dragons Insider Subscriber to use it.
It's browser-based and runs in Microsoft Silverlight (it doesn't work in Linux with Moonlight. Sigh).
On a side note, if you do use the Character Builder, you can upload that info to http://iplay4e.appspot.com and use it to dynamically keep track of your character.
Myth Weavers has a decent browser based 4e sheet that does an OK job of keeping track of simple stuff.
I'm sticking this in here because it was part of a redundant question I asked about this subject, but I'm definitely looking for more free options.
4th Ed Excel Character Sheet might do what you want.
Lone Wolf Development's Hero Lab is the best commercial character builder, and it supports 4e as well as 3.5e. Pathfinder, Savage Worlds, and many other game systems. I've used it a while and specifically baked it off against PCGen and RPGXplorer and it beats the pants off both.
Then besides a builder, it has full functionality to track in-play stuff, apply conditions, make rolls, etc.
The free and venerable PCGen supports 4E - it's meant to be both used to generate character sheets and to be used "live".
If you are running Windows and can get your hands on the old D&D offline character builder the character sheet with that one is interactive. However, they stopped updating it before the essentials line came out. Some (read me) prefer the format of that character sheet to the one you can print online.
I had the same question! I'm working on an (early) prototype here.
It's designed for phone and tablets and saves everything directly on your browser. There's a cloud sync feature, but you'll have to send me your Facebook profile to get access. That feature is handy for character entry, since you can type/paste everything on your PC, then sync and have it available on your phone.
I'm actively working on it on weekends, so shoot me an email if you want to help test or even contribute code. I'm focusing on UI and making it table-friendly right now. 4e is on it's way out, so I'm hoping to take a second pass at it to generalize and make it work for other games. I'm also a D&D newbie so I need help from more seasoned players to make it work.