Bulk mail from gmail

I need a small program that lets me log in to any gmail account I own and let me send X number of mails with randomly generated subjects and content (random so that the receiver's inbox doesn't merge it in the same thread due to same subject/etc) to any email ID. I would prefer if the randomly generated content and subject can be customized. It should have a receiver id field and number of mails to send field. Example of how I want it to work: I login to the program with my gmail account and in the 'number of mails to send' field, I enter, say 99. Now it sends 99 mails to the receiver ID I entered. First mail subject automatically gets generated as '1' and the body too gets filled with '1'. When it's done sending the first mail, it switches to the second mail, but changes the subject and body to '2' this time and so on, just to avoid the threads being merged in the receivers inbox due to same subject/content. I want this done as soon as possible.