Just another command line script that can update your twitter status from the command line, but in only 17 lines of code. This one also uses the SSL link to protect your username/password.

You can't follow anyone, you can't send direct messages, etc, etc, etc...it just posts a new status. No username/password is stored on your file system so you can post to different accounts with ease.

Should also work on older machines. This code was testing on Perl 5.6.1, LWP 5.69, and SSLeay 0.57.

Download here, or just cut 'n' paste from below:
#!/usr/local/bin/perl

use LWP::UserAgent;
( $username, $password, $msg ) = @ARGV;
$post = "https://twitter.com/statuses/update.json";
$ua = new LWP::UserAgent();
{ print "Failed to create UA.  Terminating.\n\n"; exit; } if ( ! ref $ua );
$ua -> timeout( 10 );
$ua -> credentials( "www.twitter.com:443", "Twitter API", $username, $password );
$ua -> credentials( "twitter.com:443", "Twitter API", $username, $password );
$result = $ua -> post( $post, { status => "$msg" } );
#Uncomment to print the status of the post
#print "Result: " . $result -> status_line . "\n";
exit 1 if ( $result !~ /200 OK/i );
exit 0;