Driving
You drive on the right side.
A lot is being written about the way of the drivers in Brazil. From my experience, the bottom line is, if you have driven in countries like Greece, Italy, Malta, or other, more chaotic places with crazy drivers and no rules (Northern Africa, India etc.), Brazil is going to be absolutely no problem to you. On the contrary, if you have never driven abroad or have only driven in the USA or other law-abiding countries (!), you may find driving in Brazil a bit disorientating.
Beware of THOUSANDS of radars. They have become a business, and they work 24/7.
Beware of trucks; they behave more or less as private cars. They will overtake you many times while in Brazil.
Beware of speed reducers; real lots of them. By that I mean these concrete huge obstacles that, if you don’t see them in time, can easily damage your car, or your head.
There is no huge police presence on streets in Brazil. I did not meet corrupt policemen in Brazil, although guides will tell you that this may happen. Beware that the “Policia militar” IS the police. They are not busy with militaries exclusively, probably a relic from the turbulent past of the country.

Electricity
220v, no adapter needed

Money
People do not accept necessarily US dollars. You will have to exchange them if you bring any. Do not bring any 1USD bills (very practical for tipping otherwise): they will exchange them on a 1/1 basis (1USD=1real), and you will lose almost half the value of your dollars. But you can always use them to light your cigars!

Eating
No real dangers there. Just use common sense.
Caipirinhas are known to be used to get foolish tourists drunk in places as Rio (Lapa) and be presented with a huge bill in the end.

Custom formalities
Beware that, if upon departure from Brazil you buy liquids above 100cl, they will be CONFISCATED upon your entry in Europe even if in the sealed airport bag,  because of shitty rules (the European airspace is better than all others…).