I used MAMP to run this site initially (it is running on my 2006 Mac Pro as I write this) but I think it would be wise to assign a dedicated server to take on the task as the site is growing and placing quite a lot of stress on my Mac. On top of that I want to mess around with Parallel VM with a view to installing Windows 8 on this Mac. Should anything go amiss or hog system resources then the website will slow. Also a dedicated server is just that - a server, and acts as one with auto restart and so on. So tomorrow I will be installing Ubuntu on a pretty powerful server, but not my main server I might add as that one is very loud and expensive to run.
The server I will be using is a HP Proliant G5, which has 2x Xeon processors running at 2.6Ghz. Not sure how much ram it has, though I should think at least 8GB (my main server has 128GB!). Anyway I know it is a fine server and well up to the job at hand. Shouldn't take me long to set up. I might well just swap the hard drives over from my main - might that is, or I will just reinstall Ubuntu from scratch.