Are you talking about replacing marker lights with blue LEDs (I believe you will also need to install white sunglasses and a bro lift,) or just going with a higher color temp on your headlights? Because if you go too high on the color temp, you will significantly degrade the performance of your headlights. Going with a true HID will give you some better lighting, but every other driver will think you're a dick if you don't do a proper conversion with the correct projector.
My $0.02? Don't do it. Installing a higher color temp halogen bulb will give you "bluer" lighting, but degrade performance. Install HID bulbs with a stock reflector, and you will be a menace to society (and need to install ballasts - I assume that's what you meant by "blastic" - so not plug and play.) If you need better lighting performance, install some auxiliary LED lighting and use only when there isn't other traffic on the road.
If you're just after looks, feel free to install a halogen bulb with a higher color temp and deal with worse performance. If you go to HIDs, you will need to do a proper conversion with the proper projector - I believe [MENTION=78705]jangoforhire[/MENTION] and [MENTION=51186]philsey[/MENTION] (among others) have done proper conversions and could offer some tips.