I modified small one from ikea a few yrs ago. Still works
http://www.mig-welding.co.uk/forum/threads/m300-worklight-for-a-tenner.36894/#post-405221
We were in Ikea yesterday because I have a very cruel wife.....
Also can fit a nice bright led lamp.
There isn't an Ikea in my village.
Be aware that it used to be the case that Ikea lamps only used their own bulbs, forcing you to source them there [another visit! ] , although they may be 'universal fit' now.
I used to have one exactly the same on my desk.