Written tutorials with screencasts, published by Tuts+.
How to calculate depreciation using Excel or Google Sheets
How to calculate present value & net present value using Excel or Google Sheets
How to calculate internal rate of return using Excel
How to extract data from a spreadsheet using VLOOKUP, MATCH and INDEX, using Excel & Google Sheets
How to format Excel spreadsheets using styles
How to create an Excel PivotTable using data from multiple sheets
Everything you need to make a basic PowerPoint presentation
How to use and edit master slides in PowerPoint
Inserting, drawing & editing motion paths in PowerPoint
Inserting & formatting videos in PowerPoint, and embedding videos from YouTube
How to control PowerPoint animation with the Animation pane
Tame your Outlook inbox with subfolders, rules and filters
How to set up your company e-mail with Office 365 hosted Exchange
How to create a table of contents in Microsoft Word
How to simplify Word document formatting with styles
Getting things done with Microsoft OneNote
How to host your own webmail with Roundcube (article only)
Using advanced search techniques, mostly for Google and Bing