What you would need to do is install the applications off the Leopard disk without installing Leopard, seeing as you don't have the disk with you, that's somewhat hard to do (not that it would be easy if you did have it). I suppose you could copy the applications to a flash drive and then copy them to your applications folder when you've finished, but I have no idea if they'd still work... that would probably be your best bet without the Leopard disk present.