Hi Fred,
I attended the last two picnics in Branson and you surely did miss a good time. Most from there have moved to the one in TX but I haven't made that one yet. If you do get a chance to attend a picnic be sure to do so as they are a lot of fun and informative.
I have a bench made from a kit about 30 yrs ago, a 6' heavy metal table, a 6' folding table, 6' glue up table, drawing table and desk in the shop. I also use an old horizontal file cabinet that is for the router. I still don't seem to have enough table space.
I have made a lot of trivets and most any hard wood will work. I usually use oak, walnut or cedar as have them available. After cutting I finish by soaking in mineral oil then let drip dry. Once they are fairly dry, I buff them with brown paper bag which gives a nice sheen. I use them and they work fine although I have given some as gifts and they usually wind up on the wall rather than being used.