I don´t know about you but my browser is full of bookmarks...here some I like...
Syn your calendar (several persons/devices) without google calendar
Get nextcloud, choose a cloud service (or use nextcloud to create your own cloud server at home) that can be connected. Set up the calendar for thunderbird (its using CalDAV so should also work for outlook) and use an app that can use CalDAV. You can just create several calendars (e.g.: Work, Private,…) that can be synced between (several) thunderbirds and several android/iphone mobile devices
Access outlook exchange with thunderbird
Use DavMail gateway; really helpful if your work place insists on outlook but you want to use a mail program on your home computer
Personal steps to save the planet
Compensate your Green House Gas Emissions of flying
Use idle time of your computer
Data visualisation
Your data
Create Word Clouds
www.tagxedo.com tagcrowd.com www.wordle.net
Online thesaurus
Program and make animations
processing.org scratch.mit.edu
Count words
Music Ngram Viewer
Check word frequency in many books
Make beautiful presentations
Public data
Fact-base world view
Different maps of the world
Live CO2 emissions of electricity consumption
Live marine traffic
Live air traffic
Database on Land Deals
Good Country Index
Posters about different things
www.informationisbeautiful.net
Citizen Science
Engaging projects
Find your project among 2700 research projects/events
Play but solve Puzzles for Science
Participate in different projects
Report insect
Catch a butterfly and sent it via mail
Your phone does the job
Cosmic ray detector
Monitore noise pollution
My digital solutions
Learn and perform statistical analysis
R (how to start? video, pdf-tutorial)
Analyse pictures
Work with geo-data
QGIS, Google Earth Pro, QMapShack (great for handling hand held gps)
Organize your library