I really like alton Brown's tomato sauce recipe - except that, like a lot of his recipes, it's a bit overcomplicated...
http://www.foodnetwork.com/food/reci..._20175,00.html
I don't bother seeding the tomatoes, and just kind of moosh them up since I don't have a food mill anymore (it didn't survive making baby food for the 4th kid... ;-))
but it still turns out pretty darn good.
That said, mal's recipe sounds really good - the cuke's would make for an interesting flavor combo.
How are English cuke's different from 'normal' ones?