The Pentax *ist-DS is the new-ish budget DSLR from Pentax. (I already have lots of Pentax lenses.) It's priced to compete with the Canon Digital Rebel and the Nikon D70. I could probably pick one up for $800. And I could sell the Canon Powershot S70 for probably $300.
$500 for a DSLR that I already have lenses for.
Christmas is coming up.
(Now that I look more closely, getting rid of the S70 in favor of the *ist DS would actually lose me 1MP in resolution. Hmm....)