If you mean "is there a box that can hold my digital media?" the answer is Yes. There are many alternatives.
If you mean "is there an alternative that provides anything close to the performance and ease of use of the Kaleidescape at any price-point?" the answer is No. There is nothing on the market quite like it.
Out of the many products I've installed at home, my wife will only use the BeoSound 5 and the Kaleidescape. The user interface, flexibility, etc. is like nothing else in that it doesn't feel like you're effing with an uncooperative computer. That's been the charm of the BeoSound 5 from what I've seen. Most other boxes take a lot of fidgeting on a computer of some sort (somebody mentioned Handbrake which made me chuckle. I think I'd rather sit in bumper to bumper traffic!). They are very labor intensive (ripping, finding album covers, sticking to draconian naming conventions, skirting copyright laws, dragging, dropping, mapping drives, contemplating offing yourself, drinking to excess), and all that just to get a pale imitation of what K-scape does automatically.
If the Kaleidescape is out of your price-range, I personally like the Mac Mini as an stb (but don't expect the Mrs. to be on board!). I wish there was a more elegant program than Boxee or XBMC, but both are serviceable and then you can access online services like Netflix, Hulu, etc. It also has a disc drive to boot.
Still, though. If you've got the resources, the K-scape is the Rolls Royce of media servers. You won't regret it!