Community seed swaps are how a lot of old indica lines survive after the original breeder retires or a bank drops them from the catalogue. Members trade a few seeds of a preserved line for something equally rare, with the understanding that the recipient will reproduce it and pass some back. The etiquette, the preservation projects currently running and how to take part without being a leech are described on https://kushindicaseeds.com in a pinned thread. Some of the most interesting genetics I have grown never had a price tag.