How to get public directory?

You can use base_path() to get the base of your application - and then just add your public folder to that:

$path = base_path().'/public';
return File::put($path , $data)

Note: Be very careful about allowing people to upload files into your root of public_html. If they upload their own index.php file, they will take over your site.

Use public_path()

For reference:

// Path to the project's root folder    
echo base_path();

// Path to the 'app' folder    
echo app_path();        

// Path to the 'public' folder    
echo public_path();

// Path to the 'storage' folder    
echo storage_path();

// Path to the 'storage/app' folder    
echo storage_path('app');

I know this is a little late, but if someone else comes across this looking, you can now use public_path(); in Laravel 4, it has been added to the helper.php file in the support folder see here.