Cingular's 2125 Smartphone has gained a lot of attention, not because of its cool features but because of its hump. The 2125 has a lot going for it - Windows Mobile 5.0, QVGA resolution and faster data speeds thanks to EDGE. But it seems like we are more obsessed about the hump and overlooking the plus points of this Smartphone. And the
"ugly" hump is there to improve the cell phone reception.
I decided to do a little investigation. So that I can prove that the hump serves a useful purpose. Before I provide the supporting evidence, I would like to mention, that I do not work for Cingular or HTC; I do not own stocks in either of these companies.

The evidence consists of a bunch of images from the FCC's repository. And in case you are not convinced, you are free to order the hump-less i-mate SP5 or one of its cousins.

Presenting a few close-up images of the antenna module for the Cingular 2125 and Cingular SMT5600.
Figure 1: Take a closer look at the highlighted area. You can see the gold plated foil/plate extending into the hump and it runs from one end of the hump to the other.
Figure 2: This is the antenna module for the SMT5600. No hump, no extra antenna.
Figure 3: The 2125's antenna module from a different angle. Again you can see that the antenna plate goes into the hump and extends from end to end.
What does this prove? The hump is not an empty space; a left-over after the surgery that removed the Wi-Fi as some claim. I firmly believe that this Smartphone version never had Wi-Fi enabled. The hump was added to extend the antenna, so that the cell phone reception can be improved. i-mate SP5 has Wi-Fi, but it does not have the hump. Yet, T-Mobile's un-announced SDA has Wi-Fi and has a hump. The presence of the hump does not indicate Wi-Fi support.
The hump merely shows that HTC has designed Smartphones with better antennas for the North American market. GSM coverage in the US is not as good as in Europe. Cell phones with internal antennas, especially those that operate on 1900Mhz do not receive good signal. This problem is more apparent inside buildings and homes. The bigger antenna hidden inside the
"ugly" hump will go a long way in improving the reception quality, increasing the number of bars. Or as Cingular would call it -
"raising the bar." 