Post the Mysore Subject Teacher Forum workshop in the month of July'11, I am regular user of Ubuntu. I was a regular user of proprietary software from 1996, but compared to proprietary software, Ubuntu is very handy and useful to us. The reasons are below

1. In our office we use HP 1020 laser jet printer. After installing Ubuntu in my laptop I just connect our printer to my laptop and switch on the printer. I am surprised that without any software CD the printer installed to my laptop and is working fine. The same happened when I connect my Laptop to Samsung 1040 printer in the school.
2. I have used mobile connectivity for Internet from 2009, but when I reinstalled proprietary software on my computer I have to SMS or contact customer care for getting settings. Some times it takes more than 15 days for configure. But in Ubuntu within 10 minutes I configured my mobile internet to my laptop easily without calling customer care and I am enjoying fast internet compared to proprietary software Operating System. In Bangalore I am getting sufficient internet with my Mobile connectivity to Laptop by spending only 95/- Rupees.
3. My laptop battery is broken and had only 26% charging capacity, so if I am working in proprietary software when power goes, my laptop switched off immediately but in Ubuntu it works more than 20 minutes without power! -This means in Ubuntu computer efficiency goes on increasing.
4. When our computer OS was corrupted because of virus, that time, we will backup our desktop and My document files. Recently my laptop's proprietary software portion was corrupted due to virus. However there was dual Operating system, so I take back up of files from Ubuntu desktop. After installing proprietary software I install Ubuntu to my laptop, but the Ubuntu desktops welcomes me with old files and settings. This is really amazing and I never experienced it in my life with proprietary software.

This is my experience with Ubuntu.