Alan used to (and I think still does) have a hugh table from Ikea which had a perspex top, he put lights on the legs and shone them upwards.
Will smaller pieces, like small roundles you can just lift them up, flat, when you've done some painting and see if you've missed any bit and touch up whilst the paint is still wet but with larger .pieces and "floppy" items a light box is brill.
The ones is the A&B shop are good for this as they are flat, some light boxes you can get are slopped and you have to prop them everytime you use them.