Do you really want a pig as a pet? Really?? Just as when you are considering a dog or a cat, consider that a pig isn't just for a short time, it's a lifetime (for it) commitment.
That's into twelve, fifteen years or so.
Consider that it'll want to tear your house and garden to pieces, and that you really shouldn't leave it alone to get bored unless you know it's contained somewhere 'pig-proof'.
Consider that it'll need feeding, that vets cost a fortune (and they, like babies, will need attention at some time or other), and that you'll smell and won't realize it until someone lets you know! There are a variety of types of pigs out there, and they'll cost you anything from current Market price to hundreds of pounds / dollars depending on where you get it from.
Probably the smaller the better for a pet, but beware 'Micro Pigs' - insist on seeing the parents, as they can end up anything but "micro' in a fairly short space of time.
Pigs expand quickly - they can be over 180 kilos in less than a year! They need good quality housing, as they'll feel the cold like you do, and get sunstroke very easily.
They don't sweat, but do wallow, so allow for this if you live in hotter climes.
The Kune Kune (Maori for 'fat and round') is a kiwi pig that apparently makes a good pet, kept at the bottom of the garden, and walkable on a halter.
Very much an acquired taste, they have little tassels hanging off their jowls, are very fat and round, and a long way from what a commercial pigman might consider 'attractive'.
Relatively low maintenance for a pet, and fairly easily come by.
Always spend time with the breeder considering the quirks of whatever breed you might decide upon.
The so-called 'rare breeds' are slower growing and there's a variety to choose from.
Also breeders are more geared up to supplying pet owners (in order to encourage interest and preserve the dwindling gene-pool).
You might consider the Tamworth, an orange pig with a very long nose that is probably the most primitive (in the sense of 'un-improved' genetically) of breeds.
They are coarse haired (bristly) and extremely good at grubbing up rough ground: try using your pig to get land ready for cultivation - they'll clean it of weeds and slugs in no time.
Or try a local breed of pig - Essex Saddleback, Wessex Saddleback, Oxford Sandy & Black and Berkshire all spring to mind - then there are Lops and Middle Whites, Large Blacks and the classic 'Orchard Pig', the Gloucester Old Spot.
The best place for you to go to decide isn't the Internet though! Go to a county show and walk around the pig pens, talk to the breeders - then decide! All the breeds have their own characteristics and grow to different sizes.
As a pet though, steer clear of commercial breeds please, they grow too quickly and too big...
that is unless secretly you want even more out of your 'pet' (in which case, don't name it!!)