What lesser-known free software/tools do you know about that feel illegal?

Do you know any lesser-known tool that you use as a marketer that provides some very insightful information about competitors? Please share. I'll go first - dnslytics.com/reverse-adsense. You can find sites which are owned by or associated with a company. Useful mostly for researching media blogs.

Yii2 framework - I know most of you framework guys are into laravel, but Yii2 is an excellent framework for rapidly building admin apps as well. It also has a gui based crud gen tool called gii, which in my opinion is revolutionary.

I can do stuffs with it so quickly I have been accused of using chatgpt by a client lol.

But yeah, the learning curve is a little steep. If you have some knowledge of ruby on rails, it will feel super familiar.

I really hope more people use this wonderful framework and it doesn’t die out.