Kailey (trepmal)

Hide Admin Bar till cursor is near it. Front-end only.
Limited browser and theme testing*. Please report bugs before leaving a bad review.
Find me on <a href="http://twitter.com/trepmal" rel="nofollow ugc">twitter</a>
<a href="" rel="nofollow ugc"></a>* So far so good, but please report issues (include OS, browser, and theme please)!

Discreet Toolbar

Hide Admin Bar till cursor is near it. Front-end only.

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.

Discreet Toolbar vs Admin Bar Disabler