I've written about plenty of wireless mice, but few that were actually affordable, for everyday customers. Buffalo has just launched one though.
Called BSMBW09 Series, it is a wireless mouse with a modest Blue LED sensor whose maximum resolution is of 1,200 dpi (high-end ones have 5000+ dpi).
The mouse also has four buttons: two side buttons besides the normal left/right clicks.
The thumb buttons are special though, in that they bring up the Windows 8.1 Start Screen and Charms Bar, instead of doing the normal stuff (going back and forth in browsers, or down a page in documents, etc.).
It is the reason why Buffalo describes the newcomer as a Windows 8.1 peripheral really.
The BSMBW09 can last for 134 hours on a single battery and sells for 3,465 yen / $35 / €26 in black, white, silver, blue, red and pink. Or will soon enough.