Commiting old system to HTPC use

[Sixthsense]

I have a old setup which consists of the following.

E6600
XFX 680i LT
4GB DDR2
ATI 6850
Corsair 550HX
Antec 900
Pioneer SATA DVD DRIVE
Creative Fatality XFI

I'm considering in transferring my old components to a horizontal ATX HTPC case and adding tuner and DVR functionality. Any recommendations on what tuner and case i should go for? I'll be building a new gaming rig as well when the Sandy bridge boards become readily available. Although, I'll leave that to general hardware.