The IRLZ44N is a logic-level gate version MOSFET. You can switch it ON/OFF directly from an Arduino pin. I have.
On ebay I found bags of 10 for $1.56. That's 15.6 cents each. I bought 6 bags, the discount got it to 14.5 cents each.
Why 60? I don't want to run out so I got $9 worth.
Check em out Bill! I only lucked onto these while net-surfing and they do seem capable. For battery operation, they make way more sense. In a way, needing the > 10V "amplifier" that drains current whenevr it's OFF reminds me of tube heaters.
I should say "I've gotten away with switching one directly off an Arduino pin" many times. I don't know how much surge the pin might have to supply to feed the gate capacity but it's not so bad to be a quick kill or I would have gotten smoke already!
The last multi-amp logic level FETs I got were 80 cents ea for 12, IIRC 90 cents for one. And now there's these.
I did get 2N7777's, 50 for $5, but they have continuous max current at 200mA.
I wonder how much current needs to run through the nichrome wire? Or if 5V through multiple parallel strands would work as well? How much heat is needed?