I received my Canon TX1 last week, makes great HD videos, and like others looking for deals on batteries and SDHC cards. Bought two of the Sterlingtek NB4L battries and a charger. Works great, but only for a few minutes when taking 16:9 HD video, that writes 4 Gb in about 14 min. But the aftermarket battery runs only a small fraction as long as the Canon battery. Appears that the heavy drain by the TX1 causes aftermarket batteries voltage to drop much faster and the camera to shut down. The claims of 900 mAh and even some as high as 1200 mAh appear much inflated and do not apply to the drain of the Canon TX1. Would like to hear if anyone else as found a lower cost battery that is even equal to the Canon when taking 16:9 HD video.