Today, AMD announced the introduction of two new Radeon cards based on the R600 series chipset. The new Radeon HD 2400 and Radeon HD 2600 cards are DX10 supporting cards aimed at the entry level to midrange market, bringing the R600 well below the $100 price point that is critical for low cost machines.
Both of the new cards use their existing 65nm process, and due to their low power draw are both passively cooled. Given their native decoding supporting for HD video and other features, the passive cooling might make them ideal for media centers. They also both support Crossfire, though if you're going to be buying two cards you're probably looking for something more high end.
The cards are expected to be available in the second half of this year. For the somewhat faster 2600 series cards AMD is estimating a price of $90 to $149. For the slower 2400 series cards, they are estimating a very low $50 to $85, making the bottom end some of the absolute cheapest DX10 cards on the market.
You can read the full press release at AMD's site.