Spawning an independent thread or process in Ruby

Question

I may be approaching this in the wrong direction, so any help would be appreciated.

I have a Ruby script which, amongst other things, starts up an executable. I want to

Answer 1

detunized's answer should work on windows. This one is cross-platform:

pid = spawn 'some_executable'
Process.detach(pid) #tell the OS we're not interested in the exit status

Answer 2

I just tried and start doesn't block on Windows 7 x64 with Ruby 1.8.7.

system 'start notepad'
puts 'Exiting now...'

This is obviously Windows-specific.