It seems like a logical extension of Sling Media's popular Slingbox: let viewers watch their home TVs from anywhere on their cellphones, just as the Slingbox already lets them do on their PCs. But Sling has come up against a powerful foe in its quest to bring place-shifting to the small screen: cellular carriers, who are busily cutting deals with networks and other content providers, and don't want to see Sling threaten that income. "We have no immediate plans to run that service," Jeffrey Nelson of Verizon Wireless told Forbes. "What runs on our network are our services." Of course, as more carriers move to 3G platforms like EV-DO and HSDPA, which makes accessing video directly from the internet much more practical, the carriers' official offerings will be less relevant,and Sling -- which has developed a Windows Mobile version of its service -- may well become must-see TV for cellphone users.