The video discusses five extensions that can enhance the experience of using ChatGPT, a powerful language model. The first extension is called ChatGPT Writer, which allows users to summon ChatGPT on any website and can be activated with a user-specified shortcut. The second extension is ChatGPT for Search Engines, which displays ChatGPT's answers alongside search engine results. The third extension is Promptius, which allows users to use their voice instead of typing. The fourth extension is YouTube Summary, which summarizes key points from YouTube videos. The fifth extension is ChatGPT Web Extension, which includes recent information from the web and provides citations for further research. The video also briefly mentions a chatbot called "did" that allows users to have face-to-face conversations with ChatGPT. The video concludes by stating that there are many other AI tools available, some of which are quite advanced.