I went to IKEA today, and instead of being the boring trek it usually is, I found some interesting things in the kid's Halloween section.
There is a hoop skirt and tulle petticoat for sale for 12 pounds, which looks like it could be useful for mid-Victorian costumes - if you're the right height for it, i.e. short enough to fit into kid's dress-up things like me - and a strange padded ruff-like thing.
The ruff is extremely frilly and has a lot of volume, reminding me of an 18th Century bum roll that can give skirts and petticoats extra puff. It looks quite small but fits slightly above my hips, and with stays on it may fit fuller figures and around the waist too; obviously it needs some ribbon sewing on to the ends of it, as for now it is staying put on my mannequin with sheer willpower.
They're not period correct, but for 22 pounds I think they're pretty good.
(Oh, and by the way, look at the muslin fichu I made earlier! It was so simple and fun.)