Do you use Lotus Notes for your calendar, contacts and email? If so, you need 3rd party software to sync all those things to your Axim. I also use Lotus Notes and after trying several, I would recommend a product called Cadenza mNotes from Commontime.
http://www.commontime.com
They have a trial version for download for 30 days to evaluate. You have to have a key to make the program work. After 30 days, if you buy the program, they will send you a new key to continue using the program. The program just works with your desktop so no additional software is needed on the Company Servers to get the PIM and email to your Pocket PC.
This software seems to replicate the data much more so than others and it also handles accepting meetings, repeating appointments, and handles e-mail in the inbox with ease. Since most of my email is read and then delete, email on the PDA is very useful.
A Compact Flash modem would allow you to dial into networks or ISPs and use the Pocket PC Internet Explorer. If your Company has a webmail service, then you might try to Browse Notes thru your Internet Explorer when dialed in to the network. However, I haven't found the IE on the Pocket PC capable of handling this in my experience. Our Company expects the users to be using IE 5.0 or better to use the webmail application.
Hope this helps.