Nokia just announced that it's suing HTC, RIM, and Viewsonic for patent infringement in the US and Germany. All told, there are 45 patent in the various lawsuits, covering what Nokia says are proprietary technologies — i.e., not industry standards. Specifically, Nokia's patents cover hardware features like antennas, radios, and power management, as well as software features like multitasking, navigation, app stores, retrieving email attachments on mobile, "conversational" message display, dynamic menus, and certain types of data encryption.
The patents in question makes these cases slightly different than Nokia's now-settled litigation with Apple, which involved several standards-related patents that were required to be licensed under so-called FRAND guidelines; filing lawsuits over FRAND patents has become a hot-button issue under serious international scrutiny. At the same time, Nokia has a slightly harder road to proving that HTC, RIM, and Viewsonic are infringing these patents, and it's possible they can easily be designed around — HTC has been able to design around several of Apple's patents as that case progresses.
In any event, it appears Nokia has decided to pursue aggressive licensing tactics in an effort to bolster its flagging quarterly numbers; that €430m boost the company got from Apple has to have made a few accountants in Espoo quite happy. We'll track these cases and see where they go.