Yes, I was really happy that so many open source tools born on such equipment were still around and perfectly tailored for this kind of setup.
We also used to use diskless sun terminals that worked completely over the network.
It is a bit better than that though because you can have a complete server environment to yourself, and don't have to deal with timesharing.
Unless you shell out for a dedicated server, you are sharing the physical machine with other people. The cpu is probably scheduled according to the size of the instance you bought, but you might get the whole thing if your neighbors aren't running anything.