our company has a policy that if you fly out a day early and your expenses from that extra day are less than what it would be if you flew the following day, you can do that. basically, if traveling Sunday is $100 more than Saturday, and staying Saturday night only accrues a charge of $80, then it's advantageous of them to fly me a day early.

i did this at the westin la cantera in SATX. used cash and points. i put the cash portion on my expense report and just used the points out of pocket. it was worth the "loss" of points. resort was very nice, as well.