This is a follow-on to info's script to strip the time portion of a datetime or smalldatetime, leaving only the date. I found info's script interesting! When I had to do this I converted the date to varchar and back again instead of to float. Seems to work fine for me.
For most DBAs, normalization is an understood concept, a bread and butter bit of knowledge. However, it is not at all unusual to review a database design by a development group for an OLTP (OnLine Transaction Processing) environment and find that the schema chosen is anything but properly normalized. This article by Brian Kelley will give you the core knowledge to data model.