Do you really want the mon?
Chazal say "Lo nitna Torah ela leochley hamon [The Torah is only given to those who eat the mon.]" We have no mon today, so what can it mean for us? The mon came directly from Heaven, so someone who orients him/herself to connect directly to Hashem and recognize Him as the source of all sustenance would be fit for Torah. Beyond that, though, the mon came down each day with just enough for that day (except on erev Shabbos when the double portion came for the next day). That meant that the Jews in the midbar never had the feeling of security that comes from pas besalo [bread in the basket, on hand for later]. Each day was another challenge in bitachon that Hashem will provide what you need.
The way the term parnassah tends to be used today is not that you live day-to-day with bitachon that Hashem will provide but that you are comfortable -- secure in the knowledge that you have a number of baskets filled with bread and whatever else you want on hand. I get the sense that people consider the segulahs for parnassah to be guarantees of a certain standard of living that is quite different from the experience of eating mon.
For more on segula in general and this one in particular, see http://divreichaim.blogspot.com/2012/01/parshas-hamon-and-segulah-scrooges.html
Other related posts: http://kallahmagazine.blogspot.com/2008/06/ordering-miracle-or-just-shidduch.html
Get updates by liking http://www.facebook.com/KallahMagazine Follow me on Twitter @AriellaBrown and circle me at Google+ under the same name and picture. Also be sure to visit www.kallahmagazine.com and http://www.examiner.com/jewish-bridal-in-new-york/ariella-brown