This was a very simple idea I had in mind. It takes me about, I say 2-5 minutes building this. It's quite simple, really.

Stats:

Dimensions: 6x6x7 (6x9x7 with fireplace, which is optional)
Using Command Blocks: Yes
Time to build: Approximate 2-5 minutes
Materials (Least to greatest) :

1 Stone Button
1 Hopper Minecart
1 Dropper
1 Bucket of Lava
2 repeaters
2 Command Blocks
2 Hoppers
3 redstone torches
10 Redstone Dust
19 Inflammable blocks