One top pick is QuickyAI, an extension that transforms any webpage into a ChatGPT interface so you can use AI without ever leaving the page. It's got custom prompts, one-click summarization of content and the ability to chat with any webpage. It supports GPT-4 and GPT-4 32k models, and it's available with either Basic or Premium pricing plans.
Another top contender is HARPA, a Chrome extension that uses AI models for tasks like giving instant answers, summarizing content, generating content and tracking prices. It's got more than 100 web-aware commands across many subjects, and you can enable it on any website with the Alt + A keyboard shortcut. HARPA is designed to protect privacy by running on your own computer, so it's a good option if you want a powerful tool to boost productivity without worrying about what's going on in the cloud.
If you want something more flexible and easy to use, DashAI lets you use ChatGPT abilities right on any webpage. You can summarize webpages, transcribe audio and generate AI content by typing specific prompts. DashAI is available as a one-time license activation for $17 or as source code for $59, so it's a good option if you want to boost productivity without breaking the bank.