Apple certified refurbished Macs also qualify for the OS X Leopard Up-to-Date Program:
Customers who purchase a qualifying new Macintosh computer or an Apple Certified Refurbished computer from the Apple Online Store on or after October 1, 2007 that does not have Mac OS X v10.5 Leopard included can upgrade to Leopard.
Multiple Qualifying Computers on a Single Invoice
If you purchased multiple qualifying systems on a single invoice, you can either (1) purchase a Single-User Upgrade Kit for each qualifying product, at a cost of US$9.95*; or (2) purchase fewer Single-User Upgrade Kits and request the Right to Copy for the remaining qualifying products.
Mac OS X Leopard Server Up-To-Date, Leopard Xserve - Unlimited Client
Customers who purchase a qualifying new Xserve [MA409LL/A, Z0DB, FA409LL/A, G0449LL/A, G0450LL/A] on or after October 1, 2007 that does not have Mac OS X Server v10.5 Leopard Unlimited Client software included can upgrade to Mac OS X Server 10.5 Leopard Unlimited Client..."
See the Apple Leopard Up-to-Date page for full terms and conditions.
I just ordered an iMac for a customer two days ago. I'm going to send in their coupon and my $9.95 and get my copy of Leopard that way. I never install or recommend a new OS on any system that I sell until all the bugs are worked out.
I want to keep my current boot Tiger 10.4.9 OS X as-is for a while because I know there's going to be bugs & compatibility issues with some of my apps/utilities, but I still will test Leopard every now and then and probably surf and post here within it. Plus I really really want Time Machine!