They certainly exist. And even 11 buttons isn't the maximum that are sold.
Look at the Razer Naga with 17 buttons for example.
Я долгое время был пользователем OSX, и сегодня, используя мышь с прокруткой, я понял, что в Mission Control она дает нам возможность выбирать между Второй кнопкой мыши и Кнопкой мыши 11.
Если я нажимаю колесо прокрутки, то это третья кнопка мыши. Интересно, какая мышь или имеет более четырех кнопок.
They certainly exist. And even 11 buttons isn't the maximum that are sold.
Look at the Razer Naga with 17 buttons for example.
Several gaming mice have 11 buttons:
and several models have 10 (e.g., Sensei Wireless Gaming Mouse, Logitec G500)
There is. It's used for gaming, fast editing text and more. For example you can assign all keys to bold, italic or underlined text etc. It could bring you good productivity.
Anker 5000 DPI Precision Laser Gaming Mouse is one of them.
One thing to keep in mind is that not all 'buttons' are actual buttons. Instead, all mouse actions - including scrolling up and scrolling down - are seen by the computer as buttons. Thus, a standard mouse nowadays (which comes with left/right buttons and a clickable scroll wheel) already has five buttons.
Along those same lines, certain mice have scroll wheels which can be pressed to the left and two the right, which makes a single physical controller be in charge of five logical buttons.
4-6 buttons are pretty common. (Extra side buttons operated by the thumb.)
Gaming mice and special mice/track-balls/3D controllers for CAD purposes can have many more.
The buttons are not necessarily on the mouse itself. I have also seen some (mainly track-balls and 3D-controllers) that had a separate button-pad.
MMO 7 from Cyborg has 15, yet they are not usable without the driver afaik