Goldilocks Homebrewing promotes a simple, inexpensive three-container system:
- Mash Tun: 5-gallon cylindrical beverage cooler
- Hot Liquor Kettle/Boil Kettle: 8-gallon aluminum or stainless steel kettle
- Runnings Container: Graduated bucket
In practice it looks something like this:
If you’re kettle is large enough, you can try to heat all of your mash and sparge water at once, but I’ve found that it’s faster to heat the mash water, dough in, and then heat the sparge water separately during the mash. Buckets work really well as a container to collect your runnings, and many of them have volume markings, which makes it easy to see how efficiently you are mashing/sparging.
As far as I know, this is the cheapest way to set up a traditional all-grain system, and it makes great beer.