readme: add note about 'rg -uuu'

I'm not sure about putting this in such a prominent spot, and it does
bloat the introductory paragraph a bit, but it seems like an important
special case.

1 files changed, 5 insertions, 5 deletions

diff --git a/README.md b/README.md
index 3a1ed02a..b2f7dbb8 100644
--- a/README.md
+++ b/README.md
@@ -2,11 +2,11 @@ ripgrep (rg)
 ------------
 ripgrep is a line-oriented search tool that recursively searches the current
 directory for a regex pattern. By default, ripgrep will respect gitignore rules
-and automatically skip hidden files/directories and binary files. ripgrep
-has first class support on Windows, macOS and Linux, with binary downloads
-available for [every release](https://github.com/BurntSushi/ripgrep/releases).
-ripgrep is similar to other popular search tools like The Silver Searcher, ack
-and grep.
+and automatically skip hidden files/directories and binary files. (To disable
+all automatic filtering by default, use `rg -uuu`.) ripgrep has first class
+support on Windows, macOS and Linux, with binary downloads available for [every
+release](https://github.com/BurntSushi/ripgrep/releases). ripgrep is similar to
+other popular search tools like The Silver Searcher, ack and grep.
 
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