This has always been in the back of my mind - a friend wants me to drive a backup landrover while he motorbikes across Africa... easier said than done.
When I talked to some friends about it we came up with the conclusion that one way of doing it is to fly as a contrator - ie take on short term contracts, assuming you have enough hours on a relevant type. There are lots of contract jobs in Flight International. The pay is good but only because you are frequently out of work. The lenght of the gaps inbetween are surely up to you to control. More than a year though and your type ratings will need renewing...