How do you solve the problem of pie charts always having the possibility of really low values (like 0.1% or 1%) and thus really small slices. It becomes especially problematic when you want to show % labels on top of the slice.
Maybe pie charts are not the proper solution.
But if you insist on them then perhaps "pulling out" a section onClick would be the answer.
Have it so your rollovers highlight which pie section the user is hovering over. When the user gets to the small slices they're all grouped together. Selecting that group would display a larger, more readily understandable, section.
EDIT: Each chart has it's advantages and disadvantages. Pie Charts are good for showing that "these" sections are large (therefore important or worthy of notice) and "these" sections are small/inconsequential. The only time the "inconsequential" slivers are important is when it's counter-to-expectation.
If you're concerned about comparing numerical values then perhaps a pie chart isn't the best solution.
There are numerous ways to make pie charts and their labels visually appealing: DarrylGodden displays one in his post. So, you can easily improve on the visual representation but the pie chart problem remains.