almost anything in tech from building remote controlled vehicles to writing whole software programs. it depends on the child really also puzzles and other things that occupy the mind.
Many on the autism spectrum seem to gravitate to objects and like areas where they can be alone like working with computers. They have an ability to focus and visualize the way things work in unique ways. If you talk with various people on the spectrum , they can share their personal experiences about it with you. Not having to figure out expressions, moods, and cues is a plus with computers/other tech items. Having more control over what is done with them also.
Some feel more comfortable with machines than people.
I don't know the reasons why, but it's really amazing to watch my daughter on the computer. She can't easily express herself with words, but she blogs on the computer and she's a different person.
Well technology should appeal to them. After all, most of it was invented by them. My young autistic son can fix any problem on the computer and he does it so quickly and so serenely. They love computers because computers respond in predictable ways. This appeals to brains that like to systematise things. Once you learn a sequence, you have your solution forever. My son has a great memory and loves interfacing with computers.
I read a book about the history of autism when my son was first diagnosed. It was a very beautiful book. It was called "Not even wrong." It looks at autism from a very different viewpoint, giving examples of famous autistic people in our history. One of the things that I remember reading in this book was that, at Microsoft, a lot of the staff live in this sort of compound and that (the inference is that they are autistic/aspergersish) they live to work and have to be taken on organised excursions because they would not bother to do it unless it was put into their schedule. Also, the book mentions a guest lecturer who came to give a speech at this compound. She was very surprised when the audience all seemed to be looking at their laptops during her speech. She wondered why she had bothered coming at all, since she thought that they were not watching her. Someone quietly explained that they had linked their laptops to a webcam and were watching her on their screens, rather than look directly at her. How autistic can you get!