Not since Marmalade Boy or Kodomo no Omocha have I seen an anime that revolves so much around the toy merchandising as Hana Yori Dango. It is absolutely amazing how much a part in the story the toys play. Bandai is one of the sponsors of the anime, so you can guess how many toys there are for the series. As of episode 30, I have counted 6 different little gadgets used in the course of Hana Yori Dango. And the toys aren't even that cute. They seem pretty ugly to me, yet oddly funny too. Perhaps they look so funny because they must conform to the muted color palette that is used for the anime. There aren't very many bright colors to choose from in the series. And not only do the girls have the cute little gadgets. Even the guys introduce some of them. At least one of the toys is used without fail in every episode, sometimes playing a very important part in the action of the story.
The first of the toys is introduced in episode 1 by Tsukushi's friend Yuki. It is this orange heart monitor that can be used to answer questions. Ask a question, and then place your fingertips on the sensitive buttons, and the toy lights up. This toy is used constantly by Tsukushi.Tsukushi also, at some point or other, makes everyone else in the show try it too.
The second toy is also introduced in episode 1. It is a little voice memo given to Tsukushi by Makiko-chan. The voice memo may be something familiar to Marmalade Boy fans. Miki, Yuu, and Meiko used one of these a lot. You press a button on the memo, say something, and it records your voice for immediate playback. Sana-chan in Kodomo no Omocha uses one to rap with =) In Hana Yori Dango, the voice memo is used by Tsukushi and Makiko to pass messages to each other. However Tsukushi also uses it to record things she says to herself as well.
Also introduced in the first episode are the bath supplies. For a long time these items were seen only in the anime's eyecatch, in which Tsukushi is seen in a bubble bath with the F4 peeking in on her. I was pretty impressed to see them advertising for the items that weren't even used in the actual show, but only in the eyecatch :) Finally a device that pumps soap bubbles into the tub and an automatic scrubbing brush make an appearance in the course of the actual show in episode 17.
While on a date with Rui, Tsukushi sees some girls crowded around a toy vendor selling even more ugly/cute gadgets. In a show of kindness, Rui buys one for Tsukushi. This gadget is also answers questions. It has a section of 'anwsers' laid out in a grid with with light-up dots along the x and y axis. When a question is asked, and fingertips are pressed on the buttons, the dots light up, eventually leaving only 1 dot on the y axis and one on the x axis lit. By following the spot where the coordinates cross, whatever answer is in that square is the answer to your question. This toy provides some very funny instances in episode 29.
Makiko-chan once again is a supplier of a toy on the show. This time she leaves in Tsukushi's locker a secret message written in invisible ink. Next to the message is this little light that will make the writing visible when shined on the paper. This gadget is used by both Makiko-chan and Tsukushi .
Doumyouji is the provider of the next two toys. After the events in episode 17, he gives Tsukushi a pink pager so that he can contact her at any time. This pager plays an important role in the relationship betwen Rui, Tsukushi, and Doumyouji when it is lost and then found.
Finally, the second toy Doumyouji gives Tsukushi is vital in saving her very life. This toy is a little message screen that will display one kanji/hiragana/katakana character at a time, spelling out messages. Doumyouji uses it at first to spell out the word for 'clumsy idiot' to show to Tsukushi. The characters appear lit in little LED lights on a screen. The glow of the letters on the screen end up meaning the difference betweenlife and death. Later on, Doumyouji tries to write another message on it to show Tsukushi, but she fails to notice it.