pLaNt question

I don't know of any plant with 'feet' like ivy that will attach to glass, but if you're looking for something that will attach itself to ornaments, you could try Anubias nana - small, dark green leaves, has a rhizome and roots that attach to decorations. If you wanted it to appear to cover the glass, I imagine you could use small eggcrate or wide plastic needlepoint mesh - use suction cups to attach it to the glass and allow the plant to grow up it like a trellis.
Cardamine lyrata (Japanese cress) looks like ivy, but I'm not sure if it will attach to decorations - it grows both vertically and horizontally, putting out roots at leaf nodes. It's a beautiful plant. Pennywort is similar, but with less ivy-ish leaves