I read your comment yesterday in another thread Salvatore :) and tried to find some contact on you, but without success. Yes I can but it's not widely supported by hosting providers. That's pity.
Screw 'hosting providers':-) If you're going to do anything serious, you need to be root on the machine yourself. You can get a dedicated box for under $100 a month. If that's too much initially, you can split it with a few friends - I did that for one machine, and it came to something like $20 a month, for a machine that I have root on and can do basically what I want with.
We've got a GoDaddy dedicated host for $79/month. Bottom of the line model: I believe it's a 1.6GHz Celeron with 1G of RAM or something like that. It's perfect for straightening out the last few deployment issues and seeing if we can get traction before investing a lot in the site, though. We've got full root access to the box.
Slicehost is a Xen-based VPS, not dedicated. The difference between them and other VPS providers is that they do not oversell each box so you get a good price/performance ratio.
This is common. I've heard that some are waiting many weeks (or even months) to be granted a slice. The slicehost folks have recently introduced an option to prepay for your slice, bumping you up the queue.
I was lucky to get a slice the moment I signed up for it (early adopter I suppose). I have been very happy with their service.
Hello Ivan, many info about me at http://invece.org , recent news at http://antirez.com but only if you read italian... btw antirez [at] gmail d o t com