Ubik, Philip K. Dick
After reading A Scanner Darkly, I read quite a few other books by PKD, but none gave me quite the same sense of 'wow'. Until Ubik, that is. This book freaked me out, moved me to tears and made me laugh. (It also features a minor character called Edie Dorn who I fell for hopelessly.)
The Prefect, Alistair Reynolds
Not one of Reynolds' best books, but it's interesting to explore an earlier and more civilised (by some standards) period of his future history, even if it means the gorgeously baroque and gothic elements of many of his works are toned down somewhat.
What Was Lost, Catherine O'Flynn
A story divided between tales of childhood loneliness and adult disaffection, tempered with good humour and strong characterisation. It works better in its slice-of-life character-driven moments, but the plot threads come together nicely in the end.