I've been using Battery Time Remaining for a while and it has some useful features that even the old indicator didn't have (for instance, which apps are draining the battery the most).

https://itunes.apple.com/au/app/battery-time-remaining/id551...

Looks nice.

It does feel painful to give Apple 30% of $0.99 (US) in this instance.

You can also get it for free (and the source) on Github.. https://github.com/codler/Battery-Time-Remaining

PS. i especially like the notifications you can set at 100%, 15%, 5% etc battery life. very handy!

There are binaries here: (I haven't tested them.)

http://yap.nu/battery-time-remaining/

Battery Health from Mac App Store is very nice, shows a lot of information:

http://a3.mzstatic.com/us/r30/Purple20/v4/db/ec/d0/dbecd0c9-...

This looks questionable.

https://itunes.apple.com/us/app/battery-health-monitor-batte...

Not a single of the word "menu" in the description page, even. And the UI is kinda..all-over-the-place, to be honest.

Sure, iStat Menus is great.

Seconded on iStat Menus. Despite its cost, it shows a ton of useful statistics, including moving graphs of CPU activity, network IO, storage IO, etc.. It's easy to customize the display so you see just what you care about.

It's also $18 and closed-source. You might have wanted to disclose that since I mentioned free/open. Just saying.