The only hard part was remembering how to make tinydns output the proper MX records to send all my mail to gmail. This did the trick:
@plek.org::aspmx.l.google.com.:1:1800So far so good. I'm just waiting for tight integration with various Mac apps, Mail, Address Book, iSync, etc.
@plek.org::alt1.aspmx.l.google.com.:5:1800
@plek.org::alt2.aspmx.l.google.com.:5:1800
@plek.org::aspmx2.googlemail.com.:10:1800
@plek.org::aspmx3.googlemail.com.:10:1800
@plek.org::aspmx4.googlemail.com.:10:1800
@plek.org::aspmx5.googlemail.com.:10:1800
'plek.org:v=spf1 a mx include\072google.com, include\072googlemail.com ~all:3600