Every week we dip into the reader mail bag and pull out tips and tricks to share. This week we’re looking at a super simple shortcut for resizing windows, how to contain your mouse in a multi-monitor setup, and how to check your battery configuration.

Extend a Window Vertically with a Single Click

Writing in from Ohio, reader Charles shares a clever tip that was brand new to us:

It’s such a useful trick, too! We’d never even heard of it but already see several instances where it would prove to be quite useful. You can also, under Windows 7, tap a window against the upper middle edge of the screen to perform a similar center-dock and extend trick.

Jail Your Mouse on a Multi-Monitor Setup

Steve writes in with his multi-monitor quandary and the solution he found:

Great solution Steve! We’ve seen simple apps that just stick the mouse to the primary monitor but this is the first time we’ve seen an app that supports profiles and so many variables. Nice find.

My solution is an open source app I found called Mousenitor. It’s a simple little application that allows you to effectively “jail” the mouse. You can set boundaries, toggle it with hot keys, and even set up profiles for different apps and games. It’s saved me from so many headaches! Speaking of headaches, don’t set up a profile that restricts the mouse to the primary monitor, then put the Mousenitor control panel on the second monitor, and then turn it on. That was quite a puzzle to solve.

Understanding Battery Configurations

Last week we shared a reader tip about rotating batteries to squeeze out extra life. Jim wrote in with some additional insight into why this trick might not be as effective as you might hope and how you can test if it works on your devices.

Thanks for writing in Jim, while we’re sure the reader who wrote in the original tip has had good luck with the tip it’s great to hear the science behind it and how we can test our devices to see if battery rotation has any effect.

You can also tell if the batteries are in series with a cheap voltmeter (it’s a multimeter set for measuring voltage, buy on that measures up to 30 volts to be on the safe side). They’re available at Ace Hardware or similar stores. Place the positive (red) probe at the positive terminal of one battery contact and negative (black) probe on the negative pole of the battery contact at the other end. If the voltage is 2, 3 or 4 times (depending on the number of batteries) the voltage of a single battery (usually about 1.5v for AA or AAA) that is a series circuit and rotating the batteries will have negligible effect.

Have a tip or trick to share? Shoot us an email at tips@howtogeek.com and you just might see your tip featured on the front page.