One year at Thanksgiving (when we were getting ready to have a bunch of people over!) it rained cats & dogs and the area by the downspout pooled and flooded pretty badly. So I scooted down to Ace Hardware (which was open for at least part of the day - thanks Ace!) and got one of those plastic tube extensions that you can attach to the downspout and move the water away from the house.
This worked great - now the water all goes into a landscaped area away from the foundation and soaks in. But we decided to up the ante and make a little rain garden/dry creekbed to collect and distribute the water, and also look pretty!
So far, with the second real rain of the year it's working great. I can't wait for those little ferns and whatever those succulents are to get a little bigger and create more of a landscape feature.