SmoothCursor is a status bar application that provides separate controls for customizing the mouse and trackpad accelerations and a quick way to alternate between acceleration profiles using a HotKey — perfect for drawing applications and FPS games!

User-definable Hotkey
One of the most relevant features in version 2.0 is the ability to alternate between 2 profiles using an user-definable HotKey.

System Notifications
SmoothCursor will display a system notification every time a different profile is activated using Growl or Mountain Lion's (10.8) Notification Center (This feature is optional and can be disabled by the user.)

And More

• Streamlined user interface
• Always one-click away
• Supported acceleration ranges: normal acceleration (>0 to 6), no acceleration (0), inverse acceleration (-6 to <0)
• Automatically start at login (user-definable)
• Special enforce mode (preserves user acceleration settings even if some other processes try to change them)

Requrement: OS X 10.7 or later

Home Page - https://smoothcursor.com/