For the narrow view of a layout we're trying to consolidate the 'Sign Up' and 'Log In' buttons in the header to make the calls to action and click targets larger.

Any thoughts on a word or phrase that can communicate both of these ideas?

Using one or the other alone would seem to be confusing to those it doesn't normally apply to (e.g. using just 'Log In' might leave me wondering what to do if I don't already have an account.)