My most common resort is a coffee mug.
And...yes, you can leave it in the pan.
Or, you can do what my husband does....he leaves it in the pan then uses it to cook meat the next day. Yech.
My mam just puts in in a old tin (Ie baked beans, fruit) etc
I use a bowl and put a few paper towels down then when it go to clean it , I can just use the paper towels to wipe the bowl out,
I use an old coffee can with a lid to pour all my grease in. I just throw away the can when it is full, which is usually about the same time I empty another coffee can.
It is fine to leave it in the pan until it hardens, but I can't stand to leave dishes sitting that long.
It adds wonderful flavour to other egg dishes, paella or panfried chicken breasts (which tend to go too dry).
A small amount of saturated fat is not harmful, and you have to add less salt to the food as the bacon fat is already a bit salty. I also use it for green bean dishes - "stir fry" the beans in the bacon fat then let them steam in own released water, maybe only 1 tablespoon of water added.
I keep the fat in a stoneware sugar bowl, so it has a lid.
If you must throw it away, put a sheet of newspaper and 3 paper towels on a plate and pour it onto that, ready to wrap once its gone cold.
If you have no wild animals to attract, all cats and most dogs will happily eat it, too, and they can handle a lot of fat in their diets.
I usually put the grease in my dog's dry food and mix it up. He just loves it!!
I grab a bunch of newspapers and put them in the sink. Then I pour the grease on the papers slowly so it is absorbed by the papers and then I toss out the newspapers. Use the regular newsprint, not the glossy ads.
It depends on if you want to keep it. I pour it in a pot that im going to cook beans in for dinner, along with any realy hard peaces of bacon. But you can put it in anything.
A vegetable can with some paper towels in the bottom. Or drink a little can of V8, cut the top off with a can opener and pour it in there. Some cooks store it in the refrigerator to use as seasoning for green beans, eggs, etc.