I now have a couple of different hostas, all grown from seeds I collected once I learned how easy it was to gather and sow the seeds.
How to Save Hosta Seeds
An open hosta flower calling bees to visit and pollinate it.
When the flowers have been pollinated the seed pods looks like green sausages hung out to cure.
When the seeds pods are ripe they turn brown and start to split length wise. These seeds pods are far along and one seed pod is ready to release the seeds. If you notice your hosta seed pods are starting to split open while they are still green-you can go ahead and collect them then. Even when the seed pods are open most of the seeds will remain attached.
If the seed hosta seed pod is still closed, you can split it open with a finger nail and remove the hosta seeds which are black and papery. Gardeners who don't have time to check on the progress of seed pods every day can cut the flower stalk when it looks like the pods are ripening and place it in a vase of water to finish ripening indoors. I've also cut the flower stalk and placed it in a paper bag and let the pods open and release the seeds as they dry
Here's a video from my garden that shows a couple of bees pollinating the hosta flowers.
The hilarious comment by Garden Faerie below reminded me that one day while walking my foster brother to school, I stopped to collect some hosta seeds that were hanging out of a fence and over a sidewalk. I was bent over gathering the pods when he started screaming; "They're coming! Run, MrBrownThumb, RUUUUUN!!!!" When I looked up he was half a block away, his backpack bouncing like mad. It turned out he saw someone coming out of the house and he was sure we would be arrested for taking the seeds.