The key to getting this to work is making sure that GEM_HOME is set to somewhere you have write access too:
Here is it failing: $> gem install twurl ERROR: While executing gem ... (Gem::FilePermissionError) You don't have write permissions into the /usr/lib/ruby/gems/1.8 directory. [1] 9286 exit 1 gem install twurl Here is it working: $> export GEM_HOME=$HOME $> gem install twurl Successfully installed oauth-0.4.3 Successfully installed twurl-0.6.2 2 gems installed Installing ri documentation for oauth-0.4.3... Installing ri documentation for twurl-0.6.2... Installing RDoc documentation for oauth-0.4.3... Installing RDoc documentation for twurl-0.6.2... TjL -- Twitter developer documentation and resources: http://dev.twitter.com/doc API updates via Twitter: http://twitter.com/twitterapi Issues/Enhancements Tracker: http://code.google.com/p/twitter-api/issues/list Change your membership to this group: http://groups.google.com/group/twitter-development-talk