6.0.8, 7.0.1 and 7.5.3 (+ the 7.5.5 update) are available free, but afaik only apple is allowed to distribute them. Not that they will chase anyone for distributing them.

Other OS's (older or newer) are not included int his as far as i know (but the same goes, is apple really going to chase someone distributing OS 1.1)