There have been some sporadic issues with SH107 in the past few days - it has been discussed in this thread:
SH107
It was narrowed down to some strange issues with the spam filtering, and one site that contains a shoutbox (can act as a mini-DoS against the server) which is believed to be the main problem with the server (about 2 days worth of sporadic slowdowns).
That area of their site was disabled, and immediately the load came back down.
root

sh107 [~]# w
17:23:42 up 58 days, 4:01, 2 users, load average: 2.49, 3.33, 5.03
Their site is still being "attacked" so we are also removing their DNS record..