Following are some of the registry tweaks for Windows Mobile 5 and 6. Make sure you have a registry editor like SK Tools installed on your Windows Mobile.

Enable ClearType in Landscape mode

To enable ClearType in Landscape mode: HKLM\System\GDI\ClearTypeSettings\OffOnRotation = 0 (DWORD decimal)

To disable: HKLM\System\GDI\ClearTypeSettings\OffOnRotation = 1 (DWORD decimal)

Make WM ask where to install a program

An alternative method of making WM5 ask where to install a program is by adding the “/askdest” option to the Windows CE loader:
HKCR\cabfile\Shell\open\command = ‘wceload.exe “%1″ /askdest’ (REGSZ string, no quotes)

Change the location of My Documents

Documents are opened in and saved to the device’s internal storage by default. You can change this location to, for example, your Storage Card:

HKLM\Software\Microsoft\Windows CE Services\FileSyncPath = “\Storage Card\My Documents” (REG_SZ string, no quotes)
To return to the original location:

HKLM\Software\Microsoft\Windows CE Services\FileSyncPath = “\My Documents” (REG_SZ string, no quotes)

Change the location of Temporary Internet Files
When browsing the web, pages and images are saved in the ‘Temporary Internet Files’ location. You can change this location to, for example, your Storage Card:

HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders\Cache = “\Storage Card\cacheie” (REG_SZ string, no quotes)
To return to the original location:

HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders\Cache = “\Windows\Profiles\guest\Temporary Internet Files” (REG_SZ string, no quotes)