If you need to check email on the road, consider a PDA.  It may seem more expensive at first, but the wide range of functionality combined with a flat rate service may make the cost justifiable.  

Be sure to verify that service will be available in the areas that you will be traveling.  As a fallback, you can also get a wired modem to check your email. The fact that you don't have to carry and setup a laptop to check your email makes this a very attractive benefit for many business travelers.

If you don't want to carry around a PDA, the best option is to get a web enabled PCS phone.  The cost of the basic service can be very reasonable. Monitor the usage of your wireless web access.  If it becomes great enough, consider a flat rate pricing plan (some phone carriers will offer this option in the future).

Which wireless service should you use?

OmniSky offers a flat rate pricing plan for Palm V users.

Sprint PCS offers a range of services for wireless web users.

Choose Wireless Device and 
Wireless Service

Decide what type of wireless device will meet your needs

Web enabled phone (Samsung, Nokia, etc.):

Pros:
1. Compact and streamlined design
2. Combined functionality of a phone with a wireless browser
3. Easy to sign-up for web services
4. No need to buy a wireless modem
5. Service available in most metropolitan areas

Cons:
1. Small display area
2. Difficult to enter information
3. Expensive per minute charges
4. Difficult to send and receive email

PDA (Palm V, PocketPC, etc.):

Pros:
1. Relatively large display area
2. Many devices with color capability
3. Services available that offer flat rate charges
4. Combined functionality of a data assistant with a wireless browser
5. Able to send and receive email

Cons:
1. Must purchase a wireless modem
2. Few wireless providers to select from
3. Coverage not available in some metropolitan areas

Palm VII:

Pros:
1. Modem built into the PDA
2. Flat rate pricing now available

Cons:
1. Must download proprietary "web clippings"
2. Signal subject to interference from walls and other objects
3. Limited coverage
4. Must use proprietary network