You can attach: jpg, jpeg, gif, zip, txt, log, pdf, png, swf, fla, doc, rtf, psd, eps, esp, xls, xml, mp3, wav, swi, docx, dotm, mp4 files.
* If you'd like to attach a file format that's different to the ones listed above. Contact me, and i'll let you know if it's a file format i'll allow.