In Windows, I always try to find a decent Hex editor (HxD is a rather good one).
Now, since I am only interested in reading a file in Hex format, od is a good linux command, which is also available to use in Cygwin, to dump file in Hex (By the way, OD means Octal Dump)
To see dump in Hexadecimal, do the following
od -h your_file.txt
Another useful dump is to dump a file in ASCII, do the following
od -c your_file.txt