Peter Westwood

Makes that admin bar always visible even for logged out users
Adds a login button when logged out, registration button if registration is enabeld and the shortlink also displays when available.

Logged Out Admin Bar

Makes that admin bar always visible even for logged out users

Scott Kingsley Clark

Pretty easy setup.. just install and activate it on the site of your choice (or network activate) and set up the settings however you’d like.
This plugin supports both Per-Site and Per-Network (WordPress Multisite) settings, so you can fine tune your options based on your needs.
Other plugins you might be interested in:
<ul>
<li>Showing the Admin Bar in more cases – <a href="https://wordpress.org/plugins/always-show-admin-bar/" rel="ugc">Always Show Admin Bar plugin</a></li>
<li>Showing the Admin Bar to logged out users – <a href="https://wordpress.org/plugins/logged-out-admin-bar/" rel="ugc">Logged Out Admin Bar plugin</a></li>
<li>Customizing the Admin area based on role – <a href="https://wordpress.org/plugins/adminimize/" rel="ugc">Adminimize</a></li>
</ul>

Admin Bar Disabler

Pretty easy setup.. just install and activate it on the site of your choice (or network activate) and set up the settings however you'd like.

Logged Out Admin Bar vs Admin Bar Disabler