Nichrome wire
Nichrome wire is used on RepRap domain as an heater element on Extruder or/and Heated Bed. Outside RepRap domain, it is also used as heater element on toasters and ovens.
Nichrome wire can be insulated or not. If you get it without insulation, you can use Kapton tape to insulate it (even for using on Extruder). You can also buy on the shops the insulation for it.
You can buy on online shops the nichrome wire, however it tends to be expensive and they sell just a few amount of it, meaning that if you make a mistake you will need to buy more again and wait more time for it to arrive at your home. The best solution is to found on local shops, typically on ones that sells parts for electric machines. the same shops usually also sells the insulation.
See here a picture of the Casainho extruder using nichrome wire and insulation, both bought on local shop.
There are a few online shops that sells nichrome wire:
