I just got my phone bill, from our May trip. We used a pay phone with our AT&T calling card to check our messages, and a couple of calls to let our parents know that we arrived, room #'s etc.
A 1 minute call to check our voice mail, was $5.88. 22 total minutes, cost $49.52. The really bad part is the bill cut-off was only half-way through our trip, so I get next months bill to look forward to as well.
I will definately make the extra trip to Sam's. I could just kick myself for not taking the time.