DUBAI (Reuters) - Started at the height of the economic boom and built by some 12,000 laborers, the world's tallest building will open on Monday in Dubai as the glitzy emirate seeks to rekindle optimism after its financial crisis.

Burj Dubai, whose opening has been delayed twice since construction began in 2004, will mark another milestone for the deeply indebted emirate with a penchant for seeking new records.