Personally, I have begun using MacStumbler so that I know where all the wireless networks are around my campus ... so I know which classes I can be online in ... to look up course material, really!
Check the link and give feedback so that we can finally catch up to the other platforms in wireless scanning capabilities.
[Editor's note: This article has been in the submission queue for a while; I was debating the merits of posting it, given the potential for abuse. However, it also has great potential benefits for helping secure your wireless networks. For example, if you wish to prevent your network from being seen by MacStumbler (or anyone using other Windows or UNIX-based stumblers), you'll need to go to the Airport Admin Utility and enable the checkbox that reads "Create a closed network". With this box checked, your network will be invisible to MacStumbler (and, I believe, the other stumblers, but I haven't tested those).]

