So what would it be like if medical science could shave a good half-century off your life, allowing you to turn the whole bodyclock back?
Peter Hamilton takes on the intriguing idea in his black comedy of errors, 'Misspent Youth' (Macmillan, November 2002). But to say that he gives it stellar treatment would be misleading, especially if you identify this writer with grand space opera.
Very much down to earth in the year 2040, the Brits have been dragged into a federal Europe. Jeff Baker becomes the first beneficiary of a fantastically expensive rejuvenation process, paid for by Brussels, keen to prove that the "old continent" is right up front on the world stage.
Youth is Jeff's reward for inventing the datasphere, based on solid-state memory crystals, replacing the Internet. The 78-year-old scientist is seen as a worthy choice, since instead of amassing a fortune from his work, like some near-future Bill Gates, he magnanimously refused to patent his achievement and turned it over to the public domain.

Trouble starts almost as soon as Jeff quits a German clinic to rejoin his young wife, a high-flying former model turned bitchy by boredom, and their 18-year-old son, Tim.
The lad, who's trying to make sense of his failures and unexpected successes with the opposite sex, soon finds that having an adored father turned back into a man in his early 20s is more of a challenge than ever he expected. Especially when Dad's uncontrollably randy and can't be trusted around the girls Tim manages to bring home.
As for Mum, life was fine when she and Jeff had an "arrangement" regarding her lovers, but now he's young enough — in body, at least — to question that deal, things get complicated.
Even his old drinking buddies down at the pub are suddenly just that: old!
Enter the media hordes, of course, along with the police. Before Jeff's even back home, a Europol squad moves into house and village, a measure which doesn't go down at all well with the family.
The politicians impose tight security. It's not in a mere four decades that all Britons are going to shrug off mistrust and take kindly to being integrated into an enlarged Europe or to people presented as symbols of its "success".
Underground Separatist movements use tactics which make the IRA's kneecapping technique look like school playground high jinks.
The dark side to this book lies partly in Jeff's rake's progress with his new-found lust, and partly in Hamilton's bleak political undercurrents, swelling to a climax at a huge anti-Brussels protest in London.