Glass or wood pieces
When it comes to glass or wood pipes, you may want to steer clear of boiling. Many people safely boil their glass or wood pipes, but you run the risk of weakening the glass or warping the wood if you do. So! Just be aware of that.
Instead of making pipe soup, when it comes to glass or wood apparatus a little shaking and a lot of soaking is what's called for. There are a bunch of different ways to go about this, from container variations to the choice of soaking liquid.
In terms of where this operation is taking place, you can use a large bowl that's big enough to fully submerge the pipe in liquid, or a plastic take-out box, Ziploc bag, or other tightly-lidded container.
When it comes to what to use to clean a glass or wood pipe, there are loads of options and, as it turns out, people get really territorial and weird about their personal method and want to insist to you that it's The Best Way, which is pretty un-chill, but also sort of endearing. Rubbing alcohol, vodka, Formula 420 -- those are all ones that people will evangelize about. For our purposes, we're going to use rubbing alcohol to talk about methodology, and you can swap in vodka or white vinegar or water+epsom salt or or or or or. Lots of options, is the takeaway here!
Fill the bag or container with equal parts rubbing alcohol and warm water. Then add a liberal amount of kosher salt, put the lid on or seal the zipper, and give it a good shake. Then, let it sit for 30-60 minutes before rinsing; if there's still lingering residue, use a pipe cleaner to coax the gunk out.
If you're using a bowl rather than a sealable bag or container, you won't be able to get that cool agitation effect, which means that you'll want the cleaning agent to provide that for you. Enter baking soda and vinegar! Or denture tablets and water. Things that fizz, is the idea here. Denture tabs can be dropped into the bowl and then covered with warm water; if you use baking soda, cover the piece with a good amount of the stuff then pour white vinegar over and marvel at the cool-ass volcano effect. Allow the piece to soak for 10-15 minutes then rinse with warm water.