Here something weird. Try Googling “9999999..99999999999999999999999”. It tries to load for sometime and then redirects to this strange error page.
From what I figured out from a discussion on Hacker News, “..” is an operator that is used to denote a range. So if you Google “1..10”, it searches for all the numbers from 1 to 10. As you keep increasing this range the query takes more time as the result set grows. After a certain range, it’s so big that Google refuses to accept it, thinking you are trying to start a Denial of Service attack.
There also are certain range searches for e.g. credit card number range that are also not allowed.
If you find a different/better explanation, do leave a comment.