Amazon is currently selling the Logitech MX Anywhere 2S Wireless Mouse for just $49.95. That is actually good for around $30 off of its regular price, which makes it a great time to pick up this wireless mouse, especially if you're looking for a really good mouse that's not too overly priced.
The Logitech MX Anywhere 2S is a pretty popular mouse from Logitech, largely because of the size of this mouse. It's a fairly small mouse, but not so small that it is hard or difficult to use - or gives your hands cramps. But it is small enough that it can fit in your backpack rather easily when you are traveling. This mouse also has Logitech Flow, which is just an incredible piece of software. The Logitech MX Anywhere 2S is able to remember up to three devices at once, and with Logitech Flow, you are able to move files from one device to another, using just this mouse. Which is a great way to move pictures from a tablet to a laptop or vice versa. This mouse also has pretty good battery life, Logitech claims around 60 to 90 days on a single charge, and then it uses a micro USB port for recharging the mouse, which only takes a couple of hours. So you won't need to keep AA or AAA batteries with you at all times.
This item is also eligible for Amazon Prime's free shipping. Which includes free two-day shipping, and pretty cheap (usually $3.99) next-day shipping if you need it extra fast. If you are not an Amazon Prime member yet, you can sign up for a free trial of Amazon Prime. You'll get 30 days free (if you're a student, you get 6 months), and then it's $119/year (or $59/year for students). Prime members do get a whole lot more than just free shipping though, so be sure to check out the full benefits.