Upsell

Upsell is an advertisement to buy the full version of Plants vs. Zombies. It can be accessed using either Cheat Engine through unlocking the Limbo Page or by completing the trial version which ends on Level 3-4, the level where the player finds Crazy Dave's Car Keys. It is used to tell the player that their free trial has ended.

Limbo Page
There was a page of Mini-games which were cancelled before the release of the game, called Limbo Page. The creator did not publish a visible link to this page.

Gain access to Limbo Page
Add three addresses and change all the value to 144.

See this video tutorial.

Of course, it is also possible to just get the free version and complete it.

Upsell transcript
Crazy Dave: End of the line, buddy!

Yup, you knew this talk was coming.

You wanna go further? You gotta get the FULL VERSION.

Ok, I'll level with ya, sassafras...

If you get the FULL VERSION, I'll give you more PLANTS!

LIKE THIS ONE! (Crazy Dave holding a Squash)

AND THIS ONE! (Threepeater appears on Crazy Dave's shoulder)

and later on, I'll even throw in THIS ONE! (Magnet-shroom appears on Crazy Dave's helmet.)

Why?

Because I'm CRAAAZY!!!!!thumb|300px|right|Video of the speech.

And hey...

You want action?

I'LL GIVE YOU ACTION! (the background changes to a pool level and Loonboon starts playing.)

25 MORE LEVELS OF ACTION! (the background changes again, this time to a Fog level)

40 MINI-GAMES & PUZZLES! (the background changes to the Mini-games page)

TERRA COTTA!!! (the background turns black, showing a Zen Garden Pot with an arrow above it)

IT'S ENOUGH TO BLOW YOUR MIND TO MARS AND BACK!! (the background changes again, this time to a Roof level)

Well, what are you waiting for? (the background turns, showing the "GET FULL VERSION" and "MAIN MENU" buttons)

The end. (Loonboon continues playing)

Trivia

 * The smaller version of Threepeater, Squash and Magnet-shroom can be seen here. However, they may be only smaller compared to Crazy Dave.
 * The word "Terra Cotta" said by Crazy Dave when the Flower Pot appears is actually "terracotta" in English, which means hard reddish brown baked clay. This would suggest that the Flower Pot is made with terracotta.
 * During the "40 Mini-games & Puzzles" Speech, the Mini-game Page shows there is a locked mini-game completed, though this could just be darkened and have a question mark slapped on to avoid spoilers.
 * If the player clicks on the "Get Full Version" button, it will return to main menu, if he/she has the full version. If the player has the trial version, it will open PopCap's website.
 * This scene is also used in the Xbox Live Arcade and PlayStation Network trial versions of the game, where if the player quits the game, Crazy Dave will talk to him or her in the same way.
 * If the player beats the online version on PopCap's website, it is not the full speech, but rather just the first three sentences and then the buttons.
 * The player can edit this speech if he or she has the Game of the Year version, usually hacking to unlock the LawnStrings.txt file, or the player can use Cheat Engine to edit the text.