hTC Touch Diamond is really a nice phone

How to make your Diamond to be a perfect communication and personal assistant tool?

Just follow my steps:

1 Find a nice ROM

I'd like to recommend you to try Dutty's ROM.

That's the most stable and fastest ROM I've ever used since I was using Softbank x01ht(hTC Hermes).

The latest version of Dutty's Diamond ROM is v3.3(See the original post at http://forum.xda-developers.com/showthread.php?t=411707)

2 Find a extra battery with large capacity.

I do not choose the original extra batt. pack for Diamond due to its horrible price (about €40), instead of that, I chose a pack that could used as a extra battery while plugging in. The mini USB port built-in insure this battery pack adapting to all kinds of hTC manufactured device (They all take miniUSB as a all in one port). Therefore I think such a battery pack is worth than just a extra large capacity battery only for Diamond.

3 Find some nice software to make your phone awesome

I recommend a nice shareware: PocketShield, a software that could lock you screen and provides 3 ways to unlock the device: via light sensor, via G sensor and Slide to Unlock.