A rel="" attribute is desirable for links, for example to

• limit the interest of comment spam with rel="nofollow" for anonymous wiki contributions (see Google)
• identify page tags with rel="tag" (see microformats)
• define a social network with rel="friend co-worker met ..." for contacts (see XFN)
• define a license with rel="license" (see microformats)

This patch adds this possibility to htmllink().

This one uses it for tags:

Both applied, thanks. Leaving the bug open since other parts are not implemented yet. See also rel=nofollow on external links --Joey

This can also help for css decoraton. An example of these patches in use: http://poivron.org/~nil/iki/japonesie/horizon_large/

— NicolasLimare