how to boot without power button

How can I start up my computer without using a power button? I think I have a broken power button (not completely sure, but pretty sure) and I want to know how to make it start up without using a power button. It is an ultrabook, and therefore it is not easy to take apart, attach wires to certain places in the motherboard, etc without special tools. I have already tried using a USB keyboard with a special "power" button on it, but it didn't work. I do not have a PS/2 keyboard with that function. Are there any other ways to do it? I have a warranty and could get it fixed, but I would rather get it working otherwise as it is more convenient than sending it in. Also, it is Lenovo Thinkpad Twist and I cannot remove the power button.

Turning on through a docking connector

Some ultrabooks have a docking connector and some of them allow to turn the computer on using a button on a docking station (i.e. through the docking connector). Example of such an ultrabook is Lenovo ThinkPad T440s.

If this is your case you can either use a docking station to turn the computer on or you can try to dismount the docking connector from a broken docking station to connect just the power button.

You seem to have identified all available options and have tried the convenient ones (didn't know there were keyboards with boot buttons seems odd). I can't see any solution other than taking it apart and bridging the pins / doing what ever is necessary. You may want to check your manual. It may have some tips. These aren't long term solutions however and sending it is seems much better considering you don't want to go through the hassle every time you want to start your computer.