Not a complete list by anyone's standards, but a selection of favourites that I've owned, heard or used, that stood out as special to me. This is very self-indulgent :o)

CD | Tape | Radio | Turntable | Amp | Speaker | AV | Digital | VCR | Over-rated AV

CD:
Marantz CD63SE - the sound was oh-so gutsy and powerful. Some thought it harsh, but I just loved its energy.
Audiolab 8000CD - sweet and wide open, it lifts a cloud off of any recording and presents music with much air and space and with much order.
Pioneer PDS904 - using Pioneer's own "Legato Link" DAC. I didn't like other Legato Link designs, but this CD player was good and sweet.

Tape:
Technics RSAZ7 - proves just how low noise tape can be. A superb-sounding, dynamic deck. Shame about the irritating motorised flap.
Aiwa ADF450 - was top value at about £120 (often sold for £80 new). Looked cheap but was a bargain.

Radio:
NAD 402 - smooth and lush and quite sensitive too.
Tivoli Model One - retro-appeal radio. At £99 it's over-priced (compared with some Roberts radios that offer similar sound quality), but it sounds and looks gorgeous.
Sony ICF2001D - Short Wave radio par excellence. Reliable, sophisticated and sensible.

Turntable:
Linn LP12 - OK this one comes with caveats. These days, at over £2K it's incredibly over-priced and it's fussy in set-up and requires TLC to keep it at its peak. However it has a lush and slightly weighted bass which, although not particularly natural, is very appealing and satisfying. Pick up a good example on Ebay for under £500.
Michell Gyrodec QC - stunning to look at and stunning to hear. Clean and lively and taught-sounding. Mmmmm, nice.
Rotel RQ970 - phono pre-amp. Unpretentious design and an open sound stage.
Audio-Technica AT110E Cartridge - budget (£30) price with bags of detail - a bargain.
Ortofon MC25FL - detailed and dry-sounding moving-coil cartridge.

Amplifiers:
Alchemist Forseti RC Integrated - one of the meatiest amps I've heard. Bass lines are incredibly powerful, tuneful and driven, without being bloated. It's so powerful too.
Alchemist Kraken Integrated - smoooooth! And terrific to look at.
Audiolab 8000S - it has its weaknesses - the sound can by hard and glassy and, compared to some of the others listed here, a little boring. It's just so precise, clean and has so much resolution - a very satisfying amp and brilliantly built. Ultimately I changed it because I found other amps more "fun".
AMC CVT3030a - this is certainly more fun. For all the lack of control and organised sound stage that the Audiolab gives, the AMC shirks this for fun, bags of toe-tapping energy and drive - if slightly messily presented.
IncaTec Claymore - under-valued and lacking any creature comforts. Only four inputs, a headphone socket at the rear (!) with unswitched speakers. But it can be found for less than the highly-rated Audiolab 8000A and is superior-sounding.
Rotel RA920AX - Superb value integrated amp - £120 when new and worth every penny.

Speakers:
Mission 752 - bright and zingy - especially if partnered with the wrong amp. BUT incredible detail, resolution and a HUGE image. Bass is VERY dry but so tuneful. And they're dead-efficient, so the ideal match for lower-powered, smoother-sounding amps, such as the smooth Alchemist Kraken above.
B&W CDM7SE - current main speakers. They're a pig to drive for a "commercial" domestic speaker and don't do well at lower volume levels, even with powerful amps. But when at a reasonable level they deliver an awesome image and a powerful sound stage. They're tight yet big!
Kef Model 100 - centre speaker which sounds wonderfully open and natural without any hint of "pushing" the sound at you.

AV decoders:
Yamaha DSPE800 - easy upgrade to home cinema for users of a good stereo amp and a bargain.

Digital:
Arcam Black Box 500 - makes music from digits! Connect to your MD player, DVD, PC etc and transform any cheap DAC sound into a lush and powerful performance.

Video Recorders:
Panasonic NVHS660B - brilliant performing VCR in its day, with top picture, sound and quality facilities. Sadly Panasonic's VCR reliability has let me down many times.
Sony SLHF950B - a classic Super Betamax VCR - outperforms S-VHS in both sound and video.
Sony SLC7UB - remember those top-loading, logic-controlled Betamax VCRs? These were amazing. The picture, even by today's standards, is superb for domestic video and they were built like tanks. Sadly you need a few rewind repair kits on standby for older models.

Over-rated AV - components which have been lauded by magazines for no good reason or which have sold well without the justification.

Kenwood KA3020SE - consistently rated by What HiFi as the best thing since sliced bread in the 1990s, this amp was a big pile of thin-sounding crap.

Kef Q series speakers - bright, thin and sound bad with everything. The cabinet speaker models are poorly built too. The "2005" series (sometimes known as "eggs") are lovely designs, but sound diabolical with 2-channel music. They are passable with multi-channel movies, but you're paying for design not sound-quality.

Every plasma screen ever. They just look bad. They're unforgiving of poor picture sources - ironic when you consider they are used by many with digital television - and suffer from all sorts of digital nasties, no matter what the source. Some newer HDMI equipped designs are better, but only via HDMI. Analogue inputs still look awful.

Bush MTT1 - What HiFi recommended this piece of shit as good value hifi. It is NOT "hifi" on any scale.

Linn LP12 - the irony. Yes, I said it was an all-time favourite. The problem is that people bang on and on about this deck as if it were the savior of all mankind. It has a lush sonic appeal, but it's overpriced by an order of magnitude, fussy to set up and requires endless maintenance - there are many superior designs available for less money today. There's also some controversy as to the origin of the design, from which Linn established their reputation. But die-hard Linn fans wont hear any of that.

Expensive AV amps - these are just bad value. £2500 Yamaha, Denon type-models in-particular. For less money a quality integrated stereo amplifier and add-on decoder can be purchased that will yield notably superior sound.

Apple iPod - style over substance. Low on features, awkward in operation and rapidly aging. When it came out, it was unique and special - that time has passed. Designs from manufacturers such as iRiver, Archos, Creative and more offer more powerful facilities, superior connections, easier operation and are 20-30% cheaper.