Besides the default colour schemes that Sublime provides there are many 3rd party colour schemes that can easily be installed, here are some of the best colour schemes:

Tomorrow Theme

By Chris kempson

Tomorrow Night

Tomorrow

Tomorrow Night Eighties

Install through Package Control

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Solarized

By Ethan Schoonover

Theme

Install through Package Control

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Base16

By Chris kempson

Ocean

Default

View the site for many more

Install through Package Control

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Colour Schemes

By Dayl Rees

Dayl has created loads of different schemes, here are a few of them:

FreshCut

Goldfish

Iceberg

Install through Package Control

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You can also find many more at http://devthemez.com/themes/sublime-text-2