Any suggestions for good office plants?

We have a fairly large window, which faces west onto a brick wall that is 20 feet away, so no direct sunlight but it is fairly light. Not too hot and not too cold.

There's no floor space for big plants, but we have lots of shelves and filing cabinets onto which they could go.

Chillis.

I have six Numex Twilight plants in a couple of big window boxes, a Scotch Bonnet and a Cheyenne hybrid all sitting on the windowsill near me right now.

Not only do they look nice, but they produce food.

Really common, but the Peace Lily.
Dead easy to look after and apparently cleans the air.