Direct email for me & Robin can be found on the contact info page on the website.
If the business matter involves buying Teensy or related products from PJRC, email Robin directly. For pretty much anything else, I can predict the answer will be "no". Teensy keeps me very busy. Anyone who's followed this forum can see I have an incredibly long list of Teensy developments planned. I'm definitely not available to get involved in any other business ventures, even on a paid consulting basis.
I also tend to have a 1-2 week turnaround time for emails that are anything other than an urgent customer issue. If you send me an email, know that I almost never reply promptly. Did I mention Teensy keeps me extremely busy.....