TrendMicro Rootkitbuster

... but prapper made Portable packages of a bunch of NirSoft software one of which is "AlternateStreamView" which finds files among your filesystem with alternate streams, but AFAIK it's nor really something that you need to worry to much about as far as security (someone correct me if I'm wrong here) but there are other uses for alternate streams, like saving data about a file within an alternate stream of that file (and sometimes it's fun to give people files with other information in it with steganography tools [or by playing with the internals of files for yourself] to see if they can find it and I guess you might be able to do the same kind of thing with alternate streams, IDK I haven't tried)
Note: AlternateStreamViewPortable is a Development Test release, NOT an official Portable App, and may not be entirely portable so use at your own risk.
Note2: If this app will do what you want, I'm sure prapper would like to have some feedback (is there something that's getting left behind, or some typo's somewhere)