As i mentioned in my 1rst part of the N900's Review, there're many (sometimes hidden) shortcuts and gestures that can be accessed on the N900, here's a more complete list of them :

General Shortcuts

Keyboard Shortcut	Description
Ctrl + C	Copy text
Ctrl + V	Paste text
Ctrl + X	Cut text
Ctrl + A	Select all
Ctrl + O	Open
Ctrl + N	New item
Ctrl + S	Save
Ctrl + Z	Undo
Ctrl + Y	Redo
Ctrl + F	Find/Search Bar
Ctrl + Right arrow	Move the insertion point to the end of the word
Ctrl + Left arrow	Move the insertion point to the beginning of the word
Fn + Ctrl	Symbols and characters. Symbols on the third row are entered by pressing the symbol followed by the 'Space' key
Ctrl + Backspace	Task Manager
Ctrl + Shift + P	Takes a screenshot. The PNG image file is saved in /home/user/MyDocs/.images/Screenshots/ with a timestamp in the filename.
Ctrl + Shift + X	Starts Xterm
Ctrl + Space	Switch between Input languages (Dual Dictionaries)
Double-Press Power Button	Locks device
Double-Press Shift	Caps lock on
Double-Press Fn	Locks Fn
A-Z	Start typing the name of a person to start Contacts App (Desktop Only)
Fn +	Type any number to start Phone App (Desktop Only)
Shift + Arrow Keys	Select Text
Volume Keys	Zoom In/Out or Volume Level, depending on App

Conversations

• Tap and hold on a text message: You get the option to call the person

• Swipe-from-left (as in browser) allows selecting and copying of message text

General Gestures

• Long press on Task Switch icon: Brings you back to desktop

• When getting a incoming call, turn over the device so the screen faces down towards the table surface = Silence an incoming call

• When alarm rings, turn over the device so the screen faces down towards the table surface = Snooze the alarm

• Phone App drop down menu, "Turning Control" allows you to set orientation, but also set it to launch the phone app when you turn the device to portrait. Seems to only work from the desktop.

• Using the stylus, double tap for a word or triple tap for all words

• In a sub-view of an application (e.g. Email -> Account -> Inbox) tapping and holding the Back arrow button (in the upper right corner of the screen) switches to the main view of that application [1]

Xterm Shortcuts

• Copy & Paste: Press the Selection toggle button (Arrow to left of Ctrl on the keybar), highlight the text with stylus or finger, tap Xterm menu bar, select 'Copy'. To paste text, tap menu bar and select 'Paste'.

• The Xterm keybar can be edited to add more symbols. More info: Keybar for Xterm

Keyboard Shortcut	Description
Ctrl + I	Autocomplete Filename (pressing tab does this too)
Ctrl + A	Move cursor to beginning of line
Ctrl + E	Move cursor to end of line
Ctrl + L	Clear screen
Ctrl + W	Delete the last word
Ctrl + K	Delete everything after cursor
Ctrl + U	Delete everything before cursor
Volume Keys	Change font size

Web Browser Shortcuts

• Full-Screen mode: Enter a URL directly by typing on the keyboard

Keyboard Shortcut	Description
Ctrl + N	Open a new window
Ctrl + R	Reload the current page
Ctrl + B	Open a bookmark
Ctrl + D	Add a bookmark
Ctrl + Right Arrow	Move cursor to next text-input box. Cursor must be in an input box to begin with
Ctrl + Left Arrow	Move cursor to previous text-input box. Cursor must be in an input box to begin with
Ctrl + Shift + I	Reset zoom to normal or Turn on page reflow for any zoom level
Ctrl + Shift + O	Turns on/off Portrait mode (Requires keyboard closed to work) **Incomplete Feature**
Backspace	Back
Shift + Backspace	Forward
Space	Page Down
Shift + Space	Page Up
Arrows	Move around page

Web Browser Gestures

Gesture	Description
Double tap text/image	Zoom in
Double tap text/image (when already zoomed in)	Zoom out
Clockwise circular inward motion	Zoom in
Counter-clockwise circular outward motion	Zoom out
Swipe finger from the right of the screen (outside of screen), towards left (into the screen)	Browser history
Swipe finger from the left of the screen (outside of screen), towards right (into the screen)	Hover mode. An arrow is displayed on the left. Clicking the arrow creates a pointer that can be used as a mouse to select text. Deactivate by clicking the arrow on the left. A quick hover can also be performed by swiping-and-holding finger on screen. This keeps the pointer visible until the finger is lifted. Also, pressing space performs a button click while on "quick hover". This can be handy if you just need to access a mouse-hover menu or such.

E-Mail Client

Keyboard Shortcut	Description
Ctrl + Enter	Send a message
Ctrl + R	Reply to a message

RSS Reader

Keyboard Shortcut	Description
Ctrl + R	Refresh the feed