Note: This blog post is from 2006. Some content may be outdated--though not necessarily. Same with links and subsequent comments from myself or others. Corrections are welcome, in the comments. And I may revise the content as necessary.

If you look carefully though, a search for that there or on the web will find you "Internet Information Services (IIS) 6.0 Manager for Windows XP", and that's indeed what you want.

After installing, note that it still doesn't make it possible to access IIS 6.1 servers from IIS 5's manager. Instead, it creates a new separate instance of IIS Manager 6 in your Administrative Tools alongside your IIS 5 manager. (The download page warns that it will not appear in "Computer Manager" if you also have the IIS 5.1 manager, but I saw both there and they worked fine.)

Note as well that the IIS 6 manager has no trouble accessing IIS 5 servers, so you may well just choose to use the new manager in place of the old for all your IIS management needs. Of course, it won't let you do anything on your 5.1 IIS that you couldn't do before: still no support for multiple web sites, for instance. (Though see a blog entry I did in the past on ways to get around that.)