Run custom builds from Sublime Text 2 prompt

gistfile1.json

// Create your own "my_build.sublime-build", mark it as active
// Open Preferences - Key bindings - User
// And add :
{
    // ...
    "keys": ["f8"], "command": "show_overlay", "args": {"overlay": "command_palette", "text": "Build: "}.
    // ...
}