I just got myself a low end vps as well 128/256, 15GB hdd, 500GB bandwidth, 1 ipv4 and lots of ipv6 if wanted. $15 a year - which is a no brainer to have. This one is currently located in san jose, ca -- now they are adding a new location in NY so I might have to get one there as well.
As to use, first thing I setup on mine running ubuntu 11.04 server currently is setup openvpn so I can use it as exit point if need be. Never now when you might need to tunnel some traffic. And its possible my home connection might be down.
You never know when you need shell access to test something - which is what I normally just ssh into a vm running on my home network. But it nice to have one in another part of the country to test response times with, etc.
I have no plans for mine other than a shell I can use and vpn endpoint. Yeah its running bind so I can use it as dns resolver if need be, I can use it for anything I need whenever I need it. Its a shell I can use , this is more than enough for me.
I have no other designs for its use currently - though I did think about maybe running something like seti@home or something on it
But running such things is prob frowned upon. You could always use it as a mail server, I do quite a bit of testing of smtp and dns - so I always need a shell I can bounce off of and run tests, etc.