I need a cool Twitter head/banner graphic

Industry: Business
Design details: Looking for someone to design a banner/header graphic for a Twitter account.

It's a Twitter feed that relates to Business in the country of Wales, so I'm thinking a modern graphic that combines elements of Wales and business/finance generally.

Ideas: Fresh, modern, stylised graphic of key Welsh landmarks like Menai Suspension Bridge, Caernarfon or Conwy Castle, mountains, combined with businessy stuff like a graph/chart, pound signs etc.

I'm OK with it looking modern or cartoony, but not too cheap/child like.
Target audience: Adult/Professional
Ideas for the visual style: Modern, fresh, lively, but for professional, grown-up audience
Things to avoid: Nothing that wouldn't suit professional audience, but doesn't have to be too conservative
Preferred colors: Anything. Colourful is OK
Where the design will be used: Web, twitter
Extra notes: