Andy recently posted a link to MFX’s Aether, which is a good demo, but nowhere near my recent favs:

• Moppi’s Assembly 2004 Invite (the mesmerizing flower effect is also available as a Windows screen saver!)
• Binary Flow – this invite for Assembly 2005 is pretty astounding considering it’s a 64K.
• fresh! – it really is. A great 64K, and not a glow or blur in sight 😉
• 155/95 – this won Breakpoint, and is sort of a one-trick pony, but my is that some trick (HDR, baby)
• Planet Risk – a ridiculous amount of effects. Not one falls on its face
• Breakpoint 2005 Invite – it’s a bit long, but has a real old-skool feel to it and a nice party flavor that’s really hard to resist
• we cell – ahh, gotta love that fecal blur – an impressive number of organic effects
• The Popular Demo – it’s 2 years old, but still one of my favs. The production values and execution are great

If you’re looking to get into demos, some good sites to get started:

• scene.org – the world’s largest demo repository
• Orange Juice – scene info/news
• Demoo – good picks
• pouet.net – my current favorite demo review/resource
• GFXzone – for pixel pushers
• The Happy Squirrel – demo blog