I've listed some tools which are useful for everyday productivity in the office!
ZoomIt v5.0
Screen zoom and annotation tool. Highly recommended for technical presentations or even during normal web screen sharing sessions with Clients or colleagues. Supposedly the developer has also recently added screen recording capabilities.
Office Scroll Add-In
A MS office add-in which allows you to shift+mouse scroll to navigate horizontally in Excel or Word. A very simple idea in principal, but highly recommended for Excel. Once you start using it, you can't go without it!
Web Plot Digitizer
This is a simple tool to convert image plots to useable CSV data. Unlike other tools, this tool is purely web-based, and is also semi-automated, making graph tracing very easy! Highly recommended for those wanting to do compare their results to published literature.
BGInfo
Basic tool to display information about your computer overlaid on your desktop background.