I'm in the same position, I want the internal BT card. Every dongle I have had has been a pain on both the hardware and software side (profiles go missing, dongle is placed where it gets knocked out, etc.). I have a Sony T250 with internal BT and it is fantastic! For me it is well worth the pain to get internal BT. I am going to search the forum, but if you know of a internal BT module source for the Aspire 5100-5840 (BL-51), please e-mail me or post. Thanks.