New Server suggestions - for a big VB specifically

[tfw2005]

Getting a new server, suggestions to handle these specs?

What level of server do you suggest to handle the below.

AKA, processor, ram, OS, and if you really want to get crazy, optimization specs for PHP and MYSQL settings.

30+ Domains - most with little to average average activity

2 or so VERY active - MYSQL PHP heavy

PHP/MYSQL heavily used, PHP on almost every site.

PHP includes used on many sites, pulling flat file info and
header/footer/sidebar files into a main page.

Run 2+ Vbulletin Message Boards, HEAVILY modified above and beyond core installations (possibly not well )

Mod Rewrite via .htaccess used heavily

Sites usually graphic intensive on top of all PHP/MYSQL needs

Some sites serve large static files such as MP3s and MPEGS, rushed at times
when new content added.

Need to serve MYSQL driven board systems with 1000+ users accessing large static files such as JPEGS, MP3s, MPEGS THROUGH the board system, via attachments and direct links to server files.

So, what do you all suggest to handle such a set up?

Ive seen VBs with over 1000 users online at once. Realistically, how do you acheive that, hardware/software/setting wise?

"If you had a magic wand, you would get..." type responses welcome. Later!

PS - Sorry if this is in the wrong forum, looked and didnt see a spot for it.