One of my favorite bands just released a greatest hits album. Since I already own all of their albums, I have like all but 2 songs on this album in iTunes already. I'd like to just buy the 2 songs I'm missing and tag all the other songs so that they show up appropriately in iTunes under the album. However, I want them to show up in their original album as well. I am running low on hard drive space, so I really don't want 2 copies of each file if this is possible. Anyway to tag a song to belong to 2 separate albums?