I am considering replacing my leaking 5 gallon fuel bladder with something smaller. Something off the shelf would be ideal, or I suppose I could have someone custom-make a smaller bladder and cover. A dipstick, sender, or sight tube for fuel level would also be a nice addition, as I currently have none of the above.
The general consensus seems to be that 1-3 gallons is plenty for a full day of autocross. A number of people seem to use drag racing or go-kart fuel cells with no separate bladder and no foam, and that would certainly cut down on the costs as well.
Any other ideas? What do you use?