For DH (who needs to take a packed lunch everyday because he isn't near any shops etc) I make muffins, sausagerolls (load 'em up with all sorts of vegies! and you can have them cold or hot and they're still yummo), little mini pizza's and of course left over dinner.
There is also the obvious ones... fruit... grapes are a good one! The list is endless really... the only issue i have is containing it all!

I try to keep the amount of $ i'm saving in the back of my mind as motivation!