I'm here to share some experiences and organizational details about a nearly year-long trip I recently finished through the majority of Africa. After multiple requests in both the original thread on /b/ and the archived thread on chanarchive, I'm creating a thread here on /trv/ for those who have questions or who are otherwise interested in this trip. First, some basic information about the "official" trip (scare quotes explained in a bit). For some background, check out the original thread (which was never intended to be especially informative!):
http://chanarchive.org/4chan/b/36340/what-do-you-basement-dwellers-really-know-about-africans-for-al
l-your-idiotic-nigger-banter-pic-related#comments

Company: Africans Trails (See also: Oasis)
Countries visited: the UK [Gibralter], Spain, Morocco [inc. Western Territories], Mauritania, Mali, Burkina Faso, Ghana, Togo, Benin, Nigeria, Cameroon, Gabon, Congo, Democratic Republic of Congo, Angola, Namibia, South Africa, Botswana, Zambia, Malawi, Tanzania, Kenya, Uganda, Ethiopia, Sudan, Egypt, Jordan, Syria, Turkey.
Trip duration: 43 weeks
Distance traveled: ~42,000 km

Less 'official':
Budget: $15,000 - $30,000 USD all-up, depending mostly on food/drinking habits and especially on activities
Average no. of passengers: 10-20 (my trip started with 17 and ended with 12--attrition)
Average age of passengers: 25-30 (we ranged from 21 to 60, average late 20s)
Most common nationalities: Usually commonwealth countries, esp. the UK. We had: 3 Brits, 1 Swede (5 years in London), 1 Finn, 1 German, 2 Canadians, 1 Kiwi, 3 Aussies, 2 S. Africans, and I was the only American. Almost nobody knew each other prior to the trip.