RSS:

A user's recent entries syndicated using the Real Simple Syndication XML format. Available at the URL http://www.livejournal.com/users/username/data/rss

Atom:

A user's recent entries syndicated using the Atom XML format. Available at the URL http://www.livejournal.com/users/username/data/atom

FOAF:

A user's information page using the Friend of a Friend XML format. Available at the URL http://www.livejournal.com/users/username/data/foaf

Friend-Data

A line separated list of usernames which are friends or friends-of a user. Available at the URL http://www.livejournal.com/misc/fdata.bml?user=username

Interest-Data

Interests in a line separated format. Available at the URL http://www.livejournal.com/misc/interestdata.bml?user=username

http://example.com/ljtoy.html; bob@example.com