This has been mentioned before, but I think it deserves mentioning again.

I have a T600 on T-Mobile and I just setup Call Forward to forward my cell calls to my work number while at work. Before, I would get cell calls at work, but I have spotty service in the office, so it was always a hit/miss on reception. With the Treo, it's only a few key strokes to forward or unforward the calls, very simple. On T-Mobile, it forwards the caller id of the caller, which is an added bonus. All this and these minutes do not go against my normal 'bucket', but against my 500 free call forwarding minutes a month.

At home, I have a similar issue, so I will forward my cell calls to my home number.

Added bonus - I have the Family plan and free mobile to mobile with my wife. So, if my wife calls from her cell to my cell, it gets forwarded to my work landline with much better reception. So far, * fingers crossed *, it 'appears' these minutes do not count towards my Call Forwarding minutes.

For more information on T-Mobile Call Forwarding, the following is a copy from another post that is an e-mail from a T-Mo rep about Call Forwarding:

"...There are two ways to forward calls on your handset. One will allow your phone to ring first and if you donít answer it will then forward the caller to the number you designate, normally voicemail. With the other your phone will not ring and will go directly to the number to designate.

On all our service plans we offer 500 minutes to use for call forwarding but to take advantage of those 500 minutes you would have to set up the forwarding feature so that your phone rings first. Then after you donít answer your cell phone the call is forwarded to the number youíve requested. If you answer the phone and speak with the person you begin to use your call forwarding minutes.

For example, if you set up your call forwarding so that your calls go to your home line and talk with the person who called your cell phone number originally for 10 minutes, that time would be subtracted from your 500 available call fowrading conditional minutes. Once the 500 minutes have been exhausted you would begin to use your plan minutes. If your plan minutes are exceeded you are charged your normal overage rate per minute. Also, when you have your calls forwarded to another number your voicemail greeting will no longer play. All the calls that you forward to any number will show on your bill as you are still using minutes on your phone..."