We don't know exactly what kinds of experiences Nintendo has in mind for the DSi's DSWare, beyond Brain Age variations: the rigid pricing scheme makes us think that Nintendo is exerting more control over this service than on WiiWare, or at the very least they have different plans. We're guessing it may have more applications than WiiWare (which has pretty much only the browser).
But for fun, let's assume it's a service for downloading games, just like WiiWare. Are there any WiiWare games you'd like to see adapted to the small screens? Defend Your Castle? Orbient? Anything as long as it isn't Protöthea?