Sliders are a common way for users to adjust elements with fine granularity. They can offer more choice with a smaller footprint than a drop down menu. They also offer absolute variables so the user never enters into an error state. The problem with sliders is their accessibility. They require decent dexterity since the target for the mouse is ofter small but recently I found this new method that has full keyboard support.

Accessible Sliders

This method offer full keyboard capabilities as using unobtrusive JavaScript which is a method that separates the JavaScript behavior from the page markup.

Here are some other examples of unobtrusive Javascript