Where can I find lists of extreme numbers online?

where can I find a list of extreme numbers online like Googolplexian?

what are extrenme numbers?

What possible reason would you have for needing a list of extreme numbers?

I don't know, but you could try Googleing googol, for instance. That might lead you to others. By extreme I suppose you mean large. If you were looking for small you could just take minus the largest, or if you meant small in absolute terms then it could be 1 over the largest. But 0 is the smallest absolute number.

The largest non-trivial number used in a mathematical proof was once Skewes', but that was overtaken by Graham's number, about which it was said (by Donald Knuth) that if the entire universe were ink there wouldn't be enough to write it down. That is indeed large and I'm certain there'll be an article on the internet about it.