In a press release issued today, AMD announced the released of a few new desktop processors aimed specifically at low-power yet high-performing CPUs. Modifying the 65nm single-core 3500+ and 3800+ CPUs have enabled AMD to offer the same performance you'd expect from these chips with a nice TDP of only 45W. Still higher than, say, a mobile processor, but significantly less than their 90nm cousins require.
They also introduced a new behemoth X2, the 6000+. Unfortunately, it still relies on the same X2 core we've come to love, meaning that it will not be able to stomp Core 2. The pricing on the low-power units is quite nice, sitting at a mere $88 for the 3500+. Definitely a great match for building a low-cost machine you could easily passively cool or use extremely quiet cooling with, yet still manage to have the performance of an A64. You can read the full press release at AMD's site.