In SEF Translate - Joomla module for automatic translations you could control a wide range of options, so you can be sure that it fits perfectly to your website's look and feel:

• 7 styles of translation module: Flags, Dropdown, Dropdown with flags, Plain text list vertical, Plain text list horizontal, Plain text list with flags vertical, Plain text list with flags horizontal
• 2 types of flags are available: Flat & Shiny
• 5 sizes of flags: 16px, 24px, 32px, 48px, 64px

This is language flags of size 64px: