Adding a Broadcom BCM70015 has completely revitalized my Apple TV, it goes in the miniPCI slot that previously held the WiFi card, but as my ATV1 was connected over Ethernet anyway, losing the WiFi card wasn’t an issue. As I can now run crystalbuntu and have no need to run the original Apple software I also replaced the 160GB HD with an inexpensive (99p) passive IDE to CF adapter and a 8Gb CF card (£9.97). The CF card is only slightly faster than the original HD, but the heat output should be slightly lower.