Another good trilogy i do not think anyone mentioned it yet, is The Dread Empire Series by Walter Jon Williams. its a space opera
Dread empire is ok, but full of quite silly sociological holes that make the whole premise a little silly.
Much better are Walter Jon Williams Cyberpunky themed efforts like
Ambassador of progress
Knight moves
Hardwired
Voice of the Whirlwind
Angel Station
Other unmissable's for scifi aficionados or anyone wanting to try something rather different.
On my way to Paradise by Dave Wolverton
Life during wartime by Lucius Shepard
Both these novels are as well written from a literary stand point as any booker prize winner,
and manage to pull of a wild, and heady, toxic, mixture of quite hard cyber punk and magic realism.
To truly awesome effect, cannot recommend highly enough to any and all readers ... not just genre junkies.
Vacuum flowers by Michael Swanwick
( focused insanity: the technological singularity has brought, weeds that grow in vacuum, earth taken over by a Borg-like terrifying AI driven human hive mind 'The Comprise', rebirth after death via personality backup with the disadvantage of corporate ownership )
Check it out its regarded as an early seminal cyber punk classic.
Charles Stross: Any of his "Laundry" novels. About a UK government agency that use occult networking protocols to firewall our world from infovors = Extra-dimensional entities that consume information like we eat popcorn, the darkness that wants to eat out entire existences. Heavy with Cthuloid and Lovecraftian themes ... google em.
Truly awesome.
Also by Stross:
Saturn's Children ( Fan service otakus look no further )
Halting State ( every WoW fan should read this )
Accelerando ( Classic yet twisted heavy end cyber punk/scifi )
Singularity Sky
( Classic yet twisted heavy end cyber punk/scifi a strongly Godlike AI takes over your local light cone of know space. Evicts everyone from planet earth to hundreds of planets spread over hundreds of years and light years.
Then recruits you as a secret agent, to assist in ...... )
Iron Sunrise ( Sequel to Singularity Sky )
Richard Morgan:
Any of his Takeshi Kovac scifi
( hard boiled to the core, a kind of ground zero noir style more like a crime novel style than a scifi style )
Guaranteed hooked on 1st page.
Lot of these are available free on isohunt.com ....... but if you go that route and like the books please buy them as the authors deserve the financial support.
Sorry if i repeated any suggestions.