Mine is a chrome plugin called LookupChatGPT (on Github and store) to send selected text to ChatGPT but with your own prompts. My main usage is here on HN, when I don't understand some new jargon or some complex idea I select that text, right click and do "what's this" which is a system prompt I have defined like "explain the given word or sentence or translate it. This is taken from webpage title: VAR_PAGE url: VAR_URL".

Can also just click the extension icon and ask a question, again using your own predefined prompt.

It popups up a box with response and a field to ask another question. I can re-request the response which is very helpful since you never know what's right.

Works for text selection from input boxes on a page but I don't use it that way much.

Recently used it to translate some Japanese tweets.

Made this extension mostly using GPT-4 so there is that too.