One of the most impactful and practical ways to actually save money on vacation is to capitalize on the god-given gifts that are overnight flights and overnight buses (especially overnight buses). Not only are they a great, cheap way of getting around, but they also save you money that you'd be spending for that night's accommodations. Did anybody say two birds with one stone? Yeah, we did: this is totally killing two birds with one stone.
Overnight flights, too, while not as potent as overnight buses in terms of their money-saving potential, are a great way to get around frugally.