UnDupe - Automatically removes duplicate entries from the Calendar (Date Book), Contacts (Address Book), Memos (Memo Pad), and Tasks (To Do List) (or the Franklin TaskList, if present)
UpDnHack - This is a simple hack which toggles between PgUp and PgDown hardware buttons.
I read a lot from my Palm Vx device and I found that plam's PgDown button is not convenient enough
Upload Plus - Upload and store any PC files right on your Palm. Turn unused space in your Palm into your new storage space.Add an ability to accept all PC formats with your Palm. This includes Microsoft Word, Excel, exe, html, zip, and all other formats. Simply drag and drop files into the window on your screen using your mouse, to upload and store your PC files on your Palm
UPTIME is small utility which helps you to keep track of how many times you have reset your Palm, how many times you performed HotSync and date and time of first and last Reset and HotSync operation
URLBox - What was the dialup number?
Can you give me that website again?
What was my password?
Take your Internet and e-mail accounts, your installed programs and your websites on the road in a password protected database
USB Modem (Palm OS) - USB Modem allows you to use Treo 600, Treo 650 and Treo 700p smartphones as a USB modem for connecting a desktop or notebook computer to Internet. To surf the Internet from your PC you will need only a USB cable and a Treo with GPRS/EDGE service or CDMA 1x/EvDO data plan
USB Sync Fixer - Some Palm M500's and M505's have sporadically quit Hotsyncing. One way to solve this issue is to drain the battery on the Palm until it is absolutely dead. Then charge the Palm back up and it will Hotsync again.
While this does not work on every Palm, we've found it works on about 8 or 9 out of every 10 Palms