A swarm of the tiny yellow spiders

I was repotting some plants on a table in the garden close to the house, when I saw this ball of confusion spring in to movement when I touched their web accidentally. I hadn't noticed the swarm of spiders was there, but as soon as I saw it I knew immediately what it is.

Similar baby spiders have appeared for many years in spring time in various places, sometime in the cabin itself. I suppose the parents look for protected spots, and this spring the weather has been quite warm and relatively dry until very recently.

I looked for the nest again the next day but it had totally disappeared. I like them.