Does anything like this exist? There must be. I want something that I can just log into a browzer and use.

Want my recipes/inventory in the cloud!

I've been waiting for something like this as well. With modern web browsers and AJAX and all that it could definitely be done. Nothing exists at the moment that I know of that is on par with Beersmith or Beertools Pro.

I know of something that is progress but not quite yet ready for public consumption. I've never used BeerSmith or BeerTools so I can't say whether or not it will ever match their capabilities. However, knowing the author like I do my bet is on no. It's currently pretty basic but I've been using it for my last couple of recipes and the basics are working (it's nailing my gravities, boil volumes and grist mass) and I already like it as much as my other software (BeerAlchemy). One thing I like about it is that despite being browser based you can take the whole thing offline and still have access to the entire app and all your recipes; which is great for me since I brew out in the barn and the wifi doesn't reach. If anyone is interested in testing it whenever it goes into "beta" PM me your email address and I'll pass it along. Or if there are specific features that you think are the most critical post'em here and I'll pass those along as well. As far as I know it'll be 100% free, open-source and ad-free.

Beertools pro has this online, without a yearly subscription you are limited to the number of files you can save.

http://www.beertools.com/html/generator.php
or
http://www.beertools.com/html/calculator.php

also

There's the brew-builder at Brewmasters Warehouse

http://www.brewmasterswarehouse.com/brew-builder

The only online one I've played with is beer calculus, but haven't used it for actual brewing, just for checking recipe ideas when not at home.

Here is the one I started with back in 2002. The software is pretty simple and will allow you to save your recipes online too. Beware of using the recipe database though. Many of those recipes are untested and some are just plain bad (including some of my early ones.) All in all, it is a decent online piece of brewing software with only the bare minimum of what you need.

http://hbd.org/recipator/

Wayne

I plan to try this software out myself - http://www.brewblogger.net/. Looks like it's designed to run on PHP / MySql box. I haven't used any software yet myself, but a web-based version seems to make the most sense.