Just say "no" to conditional hacks. :-) "You always have to hack for IE" is a myth. "You rarely have to hack for IE if you're rendering in standards compliance mode" is closer to the truth.
There are two things (to start with) that will make 95% of cross browser issues go away.
Understand and use a full doctype [webmasterworld.com] - though HTML5 is not in that post, it's the latest darling of the web.
Validate your documents [validator.w3.org]. You may ignore minor "warnings" that do not affect rendering (like, if you're using XHTML**, there is no "_target" for new windows) but this is the first stop to cross browser compatibility.
I haven't had to use a hack in sheesh, years. If I feel cornered to do so, I'll rearrange the way I do the layout to avoid it.
**Why most of us should NOT use XHTML [webmasterworld.com]