One box of my old received mix tapes
I used to visit this website all the time in the days when I made and exchanged mix tapes (and cds) with people. In fact when I met someone new, often a music enthusiast themselves, one of the first things we would do to cement our new acquaintance was to exchange a tape or cd of our favourite songs. You can read a lot into a person by hearing their top 20 favourite songs I believe.
I used to spend a lot of time on this site browsing through all the indie playlists, then listening to (and downloading) songs on Kazaa and Winmx. I discovered many loved songs on this site, including songs by The Decemberists, The Shins, Pedro the Lion and a myriad of other indie bands.
The dawn of the digital age has inevitably seen a diminished number of mix cds (and even tapes) exchanged, which I find rather sad. Of course you could send somebody a Spotify playlist but it does lack the magic of mix cds with their smudged handwritten playlists and rough handmade artwork. Also by creating your own playlists, you're more likely to stick to your own tastes and the music you know you'll like, rather than listening to somebody else's choices and opening yourself up to different sounds.
artofthemix is a mix-loving community of people who upload mix tape/cd playlists. There is an active forum and a search engine so you can see which playlists your songs appear in. The site is linked up to Spotify and Amazon in case you want to buy any of the songs, or indeed the whole playlist. However when I used the site a lot in the mid 2000s, if you were interested in somebody's playlist you could arrange a cd swap via post. I suspect that there are people on the site though who would be game for an old-fashioned mix cd exchange with a stranger. Waiting for the postman to put a new mix cd through my door is certainly a little pleasure I'd happily welcome back into my life.