Setting a bookmark on an object or location within a sector so you dont have to write it down. Usefull for prospecting or just favorite places.

do a search on the forum for this topic, it's been discussed to death =)

Not as "bookmarks", however.

See:
marking buoys / beacons / waypoints http://www.vendetta-online.com/x/msgboard/3/6423#

Also apparently you havn't read this...

http://www.vendetta-online.com/x/msgboard/3/7692

At least 2 of the 3 suggestions you made are in there.

Right. I should have linked to the thread and pointed him to the reference. Thanks.