How does autopopulate playlist work? (1 Viewer)

[mpab]

Hello. I'd like to know how does Mediaportal create a playlist on the fly with similar songs from other folders just by selecting a song to play. I thought it had to do with last.FM, but I haven't been able to replicate it in XBMC or find an app for my Android phone that does the same. Could you help me with that? Thank you.