As an addendum to @xmechanix's answer, I noticed through writing the contents to a file:
echo | set /p dummyName=Hello World > somefile.txt
That this will add an extra space at the end of the printed string, which can be inconvenient, specially since we're trying to avoid adding a new line (another whitespace character) to the end of the string.
Fortunately, quoting the string to be printed, i.e. using:
echo | set /p dummyName="Hello World" > somefile.txt
Will print the string without any newline or space character at the end.