Vibromatic Heart Bed

The Vibromatic Heart Bed, introduced in The Sims: Livin' Large and returned in The Sims 3: High-End Loft Stuff, is a double bed with a heart-shaped headboard.

The Sims
The Vibromatic Heart Bed, introduced in The Sims: Livin' Large, gives Sims the opportunity to "play" in bed.

To play, send a Sim to turn the bed to "Vibrate" and have that Sim lie in bed. Then, send a loved one to play in bed. Then they "play", with their Fun and Social meters rising. If the Sims are of opposite genders, the "Should we have a baby?" question may appear. However, it is possible that a baby will appear spontaneously after Sims "play" in this bed, or in custom beds cloned from it. While that isn't supposed to happen, it has been known to happen. Same-sex couples can "play in bed", though that will not produce a baby.

Using the "Vibrate" interaction on the Vibromatic Heart Bed costs §20, though many custom beds based on it were modified so that they did not charge.

If The Sims: Vacation is installed, the Vibromatic Heart Bed can be placed on Vacation Island lots.

The Sims 3
The Vibromatic Heart Bed is reintroduced in The Sims 3 with the first stuff pack, The Sims 3: High-End Loft Stuff. It gives 3 energy, so it is not the best bed to sleep in regularly, however it considerably raises the odds of conceiving a baby.

Cheat
There was one cheat commonly used when Sims were performing this action in bed. If the player engaged the "Move_objects on" cheat and moved the bed to a separate part of the lot. The player could then see the Sims basically naked and hugging while suspended in mid-air. It gave the illusion of them lying on the ground. A humorous side-effect to the event. When the Sims had completed their routine, if their energy was high enough they would climb out of the bed wherever it was placed on the lot.

The sims 2
If the expansion pack is added, sims can have the vibration bed.