I have Macbook Air 2012 model (128 GB SSD) with Mountain Lion (10.8.2) and I am having difficulties trying to configure the mail.app. When I first tried to set-up my gmail account it started to sync my Macbook with my whole gmail account which is very huge (about 10 GB). Is there any way not to sync whole mailbox? Given the limited capacity of SSD I wanted to have something like we have on an iPhone where for instance only 1000 (or less) of emails messages would be stored locally.
I suppose that most of the space required by your mails is due to the attachments. In this case you can avoid to store tham.
Indeed, in Mail.app you can configure IMAP for keeping only the text for off-line viewing and not the attachments.