These trail in autumn, winter containers. I am really shouting the praises of heucherella Yellowstone Falls. I love this foliage in a hardy pot and I equally love Redstone Falls.
A heucherella is a heuchera crossed with a tiarella. Only these two trail specifically but most flop well if planted on the rim of a container like the heuchera. They all have the lovely deep tonal blotchy marks on the foliage.