I'm still using a clone of https://del.icio.us/ that I wrote in 2004 after a fit of pique when it went down for a day or two. I use it almost daily and have amassed 11,490 links as of today, and most of them have the HTML cached.

It's kind of fun to track my interests over time by counting tag frequency, but I mainly use it out of nostalgia and for the mere constancy of it.