Are there other safe canning methods besides boiling in huge pot?

First, you have to prep your jars. Not any jar will do, it has to be a jar that your canning rings and lids will fit. You can re-use your rings, but you have to buy new lids every time.

If your jars aren't new, you need to boil them to make sure they're sterile. If they aren't bacteria may grow and ruin your hard work. You also have to make sure that the very top of the jar is smooth with no cracks, or it may not seal.

It's the heat that makes the jars seal. Have your jar lids boiling in a pot along side your jelly. The jars should be warm too, but the jelly being hot should be enough by its self to seal them. When your jelly is done, immediately transfer it to the jars and put the lids on and the rings. Then turn the jars upside down on your counter on a towel, and cover them with a towel to keep the heat in. Don't touch them until the morning.

You'll know your jars have sealed because the tops will be sucked in and won't pop when you press on them. I believe this method is called cold canning.

Your jelly will keep indeffanetly as long as it stays sealed. I've eaten caned goods from 10 years ago and they were wounderfull.

Here is what you need:

A large pot to sterilize jars (you could do it in the dishwasher if you have a sterlizing section. Keep jars warm. Pour boiling water over clean lids and keep them warm.

I have sealed jelly by flipping them over on their lids like you described. Depending on the type of fruit it should keep about a year.

The jars that don't seal, If any, keep in the fridge.

EDIT:

You will need to buy lids just about each time if they are at all worn you want a good seal each time. They aren't that expensive a couple of dollars and are worth every penny.

There is an old and safe method of making jellies and jams with paraffin to seal it. I think it involves sterile jars, boiling hot jelly or jam, and melting the paraffin in the jelly or jam so it rises to the suface to harden and seal it. I don't know the specifics, but it's ages old and safe. You should see what you can find online, but I also think it's probably on the Gulf Paraffin box, too.

Also, look in thrift stores or garage sales for canning equipment.

You don't have to buy special pots for the jars....any deepish pot will do...soup pot does nicely. Lots of times if your jars are already hot and the jam is hot they will seal themselves with out the water-bath. If they do that's just as good. If it doesn't seal you have to keep it in the fridge.