J.G. Ballard was one of my favourite authors. I recommend "Concrete Island" and "Running Wild" for readers who haven't read him yet - they are his two most accessible (and short) novels.
Also, "The Sudden Afternoon" is one of the most original and unsettling horror stories I've read.
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"If you're using half your concentration to look normal, then you're only half paying attention to whatever else you're doing." - Magneto in "X-Men: First Class"