Yay, the latest release of Mac OS X is out: Snow Leopard! It’s basically an upgrade of Leopard, with some great interface changes and a major speed boost. If you’re using Leopard it’s only £25/$29/€29 for a single user license, and £39/$49/€49 for a family pack (multiple machine installs within one family allowed). If you’re still using an earlier version, a full Box Set costs £129.
Check out the Apple Store to buy your Snow Leopard!