When we were little our family had these huge folding foam cushions we'd use as beds when guests stayed over. The flop folding cushion is like a miniature version of that, for portable softening of hard surfaces doing double duty as seating.
You may already be familiar with the Squat Module Benches by Vessel -- these cushions were designed to work with those, but we think the modern lines and functional design would add a different kind of interest to an antique-style Chinese bench just as well.
If you do use it with the Squat bench, its folding action comes in handy for storage inside the bench legs. $60 at re:modern.