I'm referring to two experiments carried out by Ian Wilson.

A gifted lucid dreamer, Wilson began to get a sense of when he was in a precognitive dream and experimented with seeing if he could affect waking reality from the dream state. On one occasion, he dreamt he was at work with a colleague and lucidly took the initiative to point his finger at his colleague's head and draw a triangle at distance with intention. Soon after, he found himself in a similar waking life situation so he went with the dream scenario and pointed his finger at his colleague's head and was able to form a perfect little red triangle that made another co-worker scream and his colleague run off to the bathroom to see what he had done.

On another occasion, he used his dream intention to reshape a dream cloud into a triangle, thus confirming he was dreaming. Shortly after the dream, he realised his dream was actualising as he walked home from a friend's house and was able to form the cloud as in the dream.

These are two examples. He says he had so many like this that he lost count!