One approach to doing this is through virtualization, like VMware, Xen, VirtualBox, etc. This provides a nice safe sandbox in which to run an OS, which ultimately runs the package one is interested in.
That's a lot of overhead to put towards running what might be a 10 microserver task. Wouldn't it be better if we could simply trust the operating system to do its job and to isolate tasks and resources in a secure manner?
If someone were to boil down a virtual machine to its minimum, I suspect you could do a lot with a machine that had 1 gigabyte of storage, 100 mhz of CPU, and 100 mb of RAM. I'd be willing to fork over some cash ($20) to help set up a contest to this end.
It should be possible to narrow down the run time environment to less than the size of damn small linux, and still be very useful.