sigh... Yet another simple plugin which needs jQuery for something which could be done in vanilla JS and still need less LOC.

Tim: A better approach would be to iterate through all children and find the maximum using elem.offset(Height|Width).

Then create a new <style> in the head for your plugin if it doesn't exist and append a new rule like:

  style.innerHTML += '#' + (elem.id || (elem.id = 'eq' + (Date.now() % 1e9))) + '>*{' + equalize + ':' + val + '}';

If you don't like this you could still use elem.style.(width|height) (and maybe even detach the container beforehand to prevent unnecessary reflows), which will be faster and doesn't require a 90KB lib.