Web Based Tools

CloudToolKit

Is actually 8 tools - Best practices analyzer, Org Compare tool, Data Compare tool, Schema Lister, Field Creator and validation/trigger switcher

https://cloudtoolkit.co/

Workbench

https://workbench.developerforce.com/login.php?startUrl=%2Fquery.php

Profile Power Tools - Mass edit profiles

https://profilepowertools.com

Google for salesforce - Search the web and only get Salesforce related results

https://sfdcsearch.com/

Json 2 apex - Create Apex based on your jason

http://json2apex.herokuapp.com/

Cert Score Calculator 

https://scuvanov.github.io/SalesforceCertScoreCalculator/

Permissions Comparison

https://perm-comparator.herokuapp.com/

Event Log Viewer

https://salesforce-elf.herokuapp.com/