Quick Online Tips: Absolutely Del.icio.us – Complete Tool Collection. Here’s a few that caught my eye:
Thumblicio.us – displays screenshots of sites by tags or most popular sites from del.icio.us.
Safarilicious – exports safari bookmarks to del.icio.us automatically.
del.icio.us pioneers – Who keeps posting the most popular links?
Linkrolls – display your latest del.icio.us bookmarks on your website.
(via tobias kopp)