If your cable box is big enough, it may be possible to rest your TV on top of it. However, this is not recommended. For one thing cable boxes are notorious for getting very hot. The heat emanating from it could rise and end up overheating the TV. It is better to put some distance between the two, and a shelf that simply rests on a TV stand, desk, or table, is a great solution.
Here’s one in black. Not much to look at, but it’s practical:
Under TV shelf for cable box pictured: OFC Express TV Stand 25 x 11 x 5.25
Of course all of this also applies to DVD players, DVR’s and VCR’s. None of them are designed to act as any type of stand. Another place people used to put their cable box was on the TV itself. In the days of cathode ray tube TV’s – the big ones – this was possible because they were several inches deep. But flat screen are, by definition, very thin, and it’s impossible to put a cable box or anything else on top of them.
I think this version is a bit nicer, if only because of the lighter color:
Under TV shelf for cable box pictured: OFC Express TV Stand 42 x 14 x 5.25, Shaker Cherry
A shelf made to rest on a desk, table or a bookcase is not a very difficult thing to construct, and so if you are handy with wood, screws, and nails, then it’s shouldn’t be too hard to build one yourself. Just make sure your shelf is sturdy, since it is going to hold an expensive piece of fairly fragile electronic equipment. If you choose to buy one pre-made, you’ll have a few things to keep in mind before buying. The most obvious consideration is dimensions.The shelf has to be wide enough for the pedestal of the TV, and it has to be high enough for you to place your cable box under it, with some room to spare, so that any heat that rises from the box has room to dissipate.You may be tempted to stack DVD boxes in that space between the box and the shelf, but this is not a good idea. Let the hot air flow freely so that it is not trapped within the cable box, causing it to overheat. These types of shelves can also be used on your office desk, in order to raise the monitor to a comfortable eye level. It could also be used to rest your keyboard on, if you find your desk is just too low.