Typically, logo designers working with Regular Businesses design with practical considerations in mind: "What does this look like in one color?", "Does it fax well?", "Can it be executed consistently across all media?", etc.
In an interesting (and well-executed) switch, the designers of the new logo for the National Maritime Museum thought outside of the logo box and created a very appropriate and beautiful 3-dimensional "splash" identity that is a pleasure to see in all its different uses (click the link to see images). As a bonus, the hidden imagery in the rendering makes the mark all the more fun to take in (do you see the 'crown' representing the Queen?).
While this is not necessarily the most practical of designs, I look forward to seeing how the identity is used over time...and whether it inspires more experimentation with the definition of a "logo."
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