Creeping Fig (Ficus pumila) is a fast growing, small leafed vine that will stick and climb up stucco and concrete. It's hardy, it gives nice coverage and texture to an otherwise frightfully boring wall and you can simply rip it off the wall if it gets to be too much. Careful with planting this on the exterior of a house since it'll probably take some of the stucco with it when you rip it off. It's also common enough to find at home depot.
We like that it provides a nice backdrop to the rest of the garden since it has such tiny leaves.
Besides this, we're a sucker for flowers and would opt for a flowering vine, like the trumpet vine but they tend not to grow as quickly and need some sort of a structure to grow up. The creeping fig will grow from the ground, up the wall with no prodding or supports, it wants to climb.