I'm so glad that you ask. My suggestion is Canning.
Does anyone still do it anymore? I'm thinking the answer is yes because when I do see canning jars and supplies in the stores. Sometimes a ton of things and then sometimes very little - so someone is buying it. I used to can a lot when my children were young. Retirement came. Moved across the country. Never thought about it anymore until this past summer. I found a BBQ Sauce that my husband and I really love. Just can't seem to make it fast enough. So I bought some canning jars and started canning it.
I wanted to try pickles and relish that I used to can years ago, but I cannot locate the recipes that I used. I'm sure that they are lost together somewhere.
So, if there is enough interest I think tried and true canning recipes would be fun.