So I don’t have to spend 2 hours searching for this yet again:
sp_change_users_login @Action = 'Report'

And, for those using WSUS looking for some nifty queries:
SELECT [LastReportedStatusTime],
[IPAddress],
[FullDomainName],
[ComputerModel],
[BiosVersion]
FROM [SUSDB].[dbo].[tbComputerTarget] order by ComputerModel, BiosVersion

SELECT COUNT([IPAddress]),
[ComputerModel],
[BiosVersion]
FROM [SUSDB].[dbo].[tbComputerTarget] group by ComputerModel, BiosVersion order by ComputerModel


Update 08/29/2005:
SELECT COUNT([LastReportedStatusTime]) AS Number,
[FullDomainName]
FROM [SUSDB].[dbo].[tbComputerTarget] group by FullDomainName order by Number DESC