HTC Lumia 900, anyone?
Nokia's Lumias differ from other Windows Phones. They contain some apps 'exclusive' to Nokia's handsets, and yes, we're using the word 'exclusively' rather lightly. They're not so exclusive anymore.
HTC's Titan is getting some love over on XDA, with custom ROMs appearing for the phone. One of them brings some of Nokia's apps straight over to the bigger phone.
The ROM you're looking for is called "WPV 8779 Nokia Edition v3". Catchy name, huh? 8779 actually denotes the phone as being post-Tango update, so you won't be using some ancient version of Windows Phone 7 if you decide you want to flash this ROM.
Installing a ROM requires a full unlock, which isn't exactly the shortest process to do. Still, once you've it done, you get Nokia's 'Camera Extras', 'Counter' and 'Contact Share'.
You're likely not going to make any friends over at Nokia by installing this ROM, but if you own an HTC Titan this is a good way to bring some exclusive apps to your phone. If you're a fan of third-party marketplaces, you're also catered to, for there's an XAP Deployer built-in.
If you're going to do this, you'll need to be willing to use English. It's the only language in the ROM, which weighs in at 384MB. Other language packs were cut out of the ROM by the developer to shave some weight off the download.
The ROM requires you changing your device info in the registry. You have to change the OEM and device name if you'd like to use Nokia's apps. Somehow, the Finnish company had prepared for this, because there's an error message if you try their apps with a standard registry.
If you're a fan of your HTC Titan but you've considered a Nokia Lumia, this might just be the best of both worlds.
Source: XDA Developers