It's the little things

Children being carried around by hand
You don't see many push-chairs and prams here.  Hardly any, actually.  The general practice seems to be carrying small children around in one's arms.  Unlike large cities in the US/UK/Canada, you see small children everywhere.  They are very family-oriented here and it seems children are taken everywhere, rather than left at home with a babysitter/grandparents/whatever.   This may be down to childcare being a luxury expense, or it may have more to do with the fact that push-chairs/strollers/prams can be prohibitively expensive here. 
But carrying children around by hand actually makes sense to me: you don't have to go through the hassle of folding and unfolding a push-chair when you get on/off a bus, you can get on and off a metro train without fuss, you're not constantly squeezing past people in busy parts of town with a massive unwieldy push-chair, etc.  I think it's a good idea. 
The other part of not having a push-chair is not having to carry around loads of baby/toddler crap with you: nappies, bottles, baby food, etc etc.  They don't seem to worry about all that malarkey here, and I've never seen anyone having a baby-related 'accident' as a result.

Everything is upside down.
By this, I mean things you expect to be cheap (cocoa, for example - Brazil produces it) are expensive and things you think should be expensive (e.g. anything involving manual labour) is cheap.  A tiny packet of pure cocoa (no sugar or additives) costs like R$10 (£3.50) and my mum got her sandals fixed the other day for R$8 (£3) - they were properly fucked and the general fix-it shop round the corner brought them back to life.  Also, things you expect to be quick and easy are slow and difficult, and vice versa.  It's a bit like stepping into 'Alice in Wonderland'. 
Example #1: we were told that dealing with the Federal Police to renew our visas would be a nightmare.  We were told to bring a book/iPod/newspaper and be very very very polite because they can be absolute bastards.  Well, apart from it taking a while to get there, none of the staff speaking even pigeon English (this department only deals with foreigners) and the building looking like something out of George Orwell's '1984', the process was very quick (just a 20 minute wait) and the staff were very helpful and welcoming - even the guards at the entrance with the bullet-proof vests, massive guns and batons were very friendly.
Example #2: In the UK, you can just walk into a bank.  I mean, you can just open the door and walk in.  That's all you need to do.  In Brazil, you cannot simply just walk into a bank.  Firstly, you must put your bag in a specially provided locker either in front of the bank or in the ATM area (a kind of purgatory for people wishing to enter the bank or get some cash out).  You only bring things with you into the bank like the key for the locker (if it has one, some just have an electronic pin code), your wallet/purse and your mobile.  There is usually a clear revolving door entrance on every bank (which is supposed to be a metal detector, but I've gone through with my metal belt buckle several times and nothing's happened), manned by a security guard (or two, often armed) which has a special clear plastic box to your right into which you put the few belongings you have left with you, so that the security guard can see what you've got.  Once you are through the revolving door, you can open the clear box on the other side and take your things back.  And that, children, is how you enter a bank in Brazil.

People help eachother
Example #1: my mother dropped her sunglasses while crossing a pedestrian crossing on Avenida Paulista, just as the lights were turning green.  All three lanes of traffic waited for her to pick them up, even after the lights had actually turned.
Example #2: when the dog had his accident at the Metro station, the staff and several passers-by came rushing to help.  They calmed my mother down, called the Veterinary Hospital to tell them to expect us, and wrote down the address so we could get a taxi - all without speaking English (our Portuguese was non-existent at that point).
Example #3: on the bus, people stand up for old/disabled/pregnant people and women with children - always.  I have seen people offer to carry other people's groceries, children, bags, help old ladies get on/off the bus, etc.

Brazilians don't trust eachother
You may think this completely contradicts my previous point, but it doesn't really.  Helping people with small things has very little to do with trust.  When it comes to money, possessions and promises Brazilians do not trust each other - and with good reason (in our experience).  The ridiculous amount of bureaucracy often has to do with counteracting the endemic corruption in this country.  In order to get our visa renewed, we had to pay money at the Bank of Brasil then get the visa renewed at the Federal Police.  When we got our CPF, we paid for it at the Post Office then picked it up at the Poupatempo.  Both measures were clearly in place to stop the Government offices getting hold of the money in cash or accepting bribes.
They tend to trust gringos - they are under the impression we keep our word and Brazilians don't.  Obviously, we know that's not entirely true.  But it is an interesting point that I have spoken to several Brazilians renting rooms or property who simply will not rent to another Brazilian because of bad experiences being screwed around, stolen from, not paid, etc.  They say they don't get the same problems when they rent to gringos.