Web servers, mail servers, file servers, directory servers, dns servers, Jabber servers, bittorrent servers, memcached, database servers, reverse proxy servers, load balancers, etc. etc. Almost all share a work profile that doesn't really benefit from swap.
You'll note that I did say *most*. Of course there exist servers that fall outside this but in my experience they're fairly rare.
So, I'm very curious, what is this somewhat common, swap-friendly type of server that I'm missing?