Multiple versions of ruby on windows

# Install ruby 1.8.6 using the one-click windows installer from:
# http://www.ruby-lang.org/en/downloads/
# Be sure to check the box to enable rubygems during the install.
# Make sure C:\bin exists and is in your path.
# Now open a command-prompt and run:

> gem install pik
> pik_install C:\bin
> pik install ruby 1.8.7
> pik use 187
> ruby -v
ruby 1.8.7 (2010-01-10 patchlevel 249) [i386-mingw32]
[etc...]
> pik default
> ruby -v
ruby 1.8.6 (2008-08-11 patchlevel 287) [i386-mswin32]

# Each version will have it's own set of gems.
# If you start with a newer version of ruby without using the one-click installer,
# when you try to install 1.8.6 with pik, it won't be able to find rubygems.