Never down the drain. We've had a few incidents in my neighborhood where the sewer pipes were clogged with fat, and a few people's basements flooded with sewage as a result.
For fats that solidify, let them do so, then pitch them in your regular garbage. Chill grease in the fridge if you need to get it to harden up. For ones that don't solidify, pour them into a sealable (hopefully non-recyclable) bottle, and throw the whole container away with your regular garbage.
It's possible that your area might accept cooking fats & oils as part of a recycling effort. Ours does for motor oil (I live in Maryland).
For restaurants, some places (eg, the state of Maryland) require a system for catching grease that's been washed down the sink. It's my understanding that they're fairly expensive (a couple thousand dollars US), but the fines for not having one installed may be even more, and they won't let new restaurants open without one.
Get good metal
A decent pair of 23 to 30 cm (9 to 12") stainless steel tongs should weigh around 125 to 150 g (4.5 to 5.5 oz); if it weighs less than this it is not going to be strong enough to be truly useful, and will probably bend and break in short order
Longer tongs, say around 35 to 40 cm (13.5 to 15.5") are great if you operate a very hot grill frequently
If it has a locking mechanism (recommended) it should only lock when the tongs are pointed up and squeezed close. It should unlock when pointed down and squeezed. This is normally achieved with a pin just below the hinge pin that is engaged when tipped up. Locks that require fiddling or two hands to operate are a pain, and often fail over time
Go for plain metal, the plastic bits never last very long or stay hygienic, and you will be adding to the rubbish pile before long
I have various tongs like this that have lasted 20 years and are still great
Cheap Chinese tongs are often just chrome plated crap steel. They are bad in so many ways: hygiene, longevity, easy of use, etc
Examples
Good tongs 23 cm with internal locking pin. Cannot bend steel with hands.
Bad tongs with silicone ends that wear out quickly. The two handed locking mechanism that jams or breaks easily
Best Answer
I agree on the Goodwill thing, but it pains me to think of putting tape on a knife blade -- someone's going to have to clean it off, and that risks someone getting injured.
Instead, find a piece of cardboard that's longer than the blade of the knife, and more than twice the depth of the blade with an inch (~3 cm) or more to spare.
Fold the cardboard in half, so it's now roughly larger than the size of the blade, and then place the blade so the back of the knife is against the fold (you can do it the other way, but you'll risk dulling the knife ... cutting paper isn't good for knives), then tape it down.
You want to make sure it's well compressed, so the knife is being held in by friction. You could always sandwich something rubbery in there with it to help with the friction.
(this is how I used to transport my knives when moving between apartments)
...
Another alternative, if you're really disposing of it, and don't mind dulling the blade, is to poke it into a piece of corrougated cardboard. Just find a piece that's longer and wider than the blade, set it on the edge of your counter, put a hand on top to hold it steady, and then slowly push the blade in.