If you're seeking a large, grey oblong on former marshland, then your search is over. The Olympic Park Legacy Company today opened its suggestions book to find a purpose for the monolithic Media Centre post-2012. The hangar-sized building, to the West of the park, is costing well over £300 million to construct - more than twice the cost of the Gherkin. Its role after the Games remains uncertain, and there have been fears that it might be knocked down if no tenants can be found. So the legacy planners are seeking any and all ideas. If occupying the building, which can be split into smaller units, tickles your fancy, you have nine weeks to submit an expression of interest.