I have been using this tool for few months now. Only thing which impresed me was the response time compared to the Management Studio.

Note: You should be careful in deleting database objects using this web-tool. No confirmations are asked!!! 

It works with servers outside the local network. However, pay attention to the points mentioned by John a few posts above.

I have it installed on windows XP service. You can simply unzip the files and create a virtual directory pointing to the folder which contains the files.

There is another open source web admin tool for sql server which looks just like the good old enterprise manager. I just gave a link to a blog since its got a nice screen shot on it the link for sourceforge is on the blog post.

http://weblogs.asp.net/rosherove/archive/2006/06/12/452008.aspx

Anyway I like it so i thought you might be interested as its also more functionla than the ms one on codeplex.

David