As reported by previous reviews, this is a small & simple yet a great plugin and very useful if you often have to create an account for collaborators and don't want to waste time annotating who and where has to access to this and that site.
I often have the need to grant temporary back-end admin access to developers, editors or collaborators and at times it happens that after months I find that some of those account are still live.
Since I have start using this little plugin I create disposable full fledged accounts that do not require username or password, they just have a time-stamp and expiration date.
Upon expiry the account is deleted automatically.
This plugin is on my list of essentials.