I have been fairly lucky, my commute is only 7 minutes to work so I do not use a lot commuting, although my gas guzzling H2 eats it up at 12mpg. A recent trip to Georgia, 2300 miles round trip while towing a boat one way cost $1000 in gas.
Filling the box truck at work at $4.20+ for diesel is tough, and paying the fuel surcharges (33% this week!) to trucking lines is getting rough.
With the added cost of a weekly 45 minute drive to the lake and feeding 3 boats however I will be paying less in gas than I spent in heating oil and electricity this winter heating our house!