Vaccines are probably one of the less exciting parts of planning travel, but a shot in the arm sure beats, say, contracting tetanus from a rusty nail.
Yesterday, I got a Hepatitis A shot in my left arm, and my partner got the same shot, plus a tetanus shot in the left arm and a polio shot in the right arm. (Hepatitis A is a two-shot procedure, so you'll have to make sure you get both. Once you have both, though, you should be set for life.)
We each got four typhoid fever pills, and we're supposed to take one every other day, first thing in the morning, on an empty stomach (and no food for an hour afterward). Interestingly, the shot covers you for two years, while the pills cover you for five.
The cost for the four shots and the eight typhoid pills was around $300. We'll go back to the kind travel nurse once we figure out how many days we'll be in Tanzania and India to get our antimalaria pills. We want to be pretty sure, as they're $2 a pill, and we have to take them daily. (Our travel nurse recommended we take Malarone, as it's supposed to have the fewest side effects, which usually include nausea and nightmares.)
The travel nurse was out of the yellow fever vaccination, so we'll also have to go back for that shot, which will be another $99 per person.
We opted for the absolutely necessary vaccines, and it will cost us about $900 (for both of us) for a year of travel. If we had taken everything (including rabies, Hepatitis B and Japanese Encephalitis), it would easily cost twice that. The Japanese Encephalitis alone would have been a three-shot procedure, costing almost $500 per person. (It's necessary if you're going to rural areas of Thailand-- which is more incentive to go to the beautiful Thai beaches instead.)
So, the take-away message is that vaccines aren't cheap, so don't forget to include them when you're planning your travel budget. If you aren't sure what you'll need, you can check the CDC (Center for Disease Control) website, which lists the travel health information by country.