The neatest idea I saw for an accordian door replacement was made out of a really cool upholstery fabric (your choice!) that had 3"+/- vertical pockets sewn in it & vertical louver blind blades in the pockets. The blades make it more substantial than just a curtain, yet not just white or woodgrain plastic like the normal accordian doors. It had snaps on the wall and corresponding one on the fabric to hold it open or closed. Looked really nice...although I didn't take any pics. If you or someone you know is halfway handy with a sewing machine, it'd be a great "customized" option.
Shari