Any camera that is capable of relatively long exposures - multiples of seconds
up to minutes. Any SLR will do, but many compacts have enough control to
achieve the longer exposure time required. If you have shutter-priority
exposure or manual exposure you'll be well away.

Using digital cameras for long exposures can result in excessive noise, but in
practise it shouldn't be a problem over a 30s exposure.

Most films suffer reciprocity failure at long exposures which means that the
usual +1 stop of exposure time no longer compensates for -1 stop of the
aperture. You may have to compensate by +1 or +2 stops. The film manufacturers
do publish the information, but as a rule of thumb, for 5 - 30s try two
exposures at +1 stop and +2 stops.

You WILL need a tripod.

Rich

You can achieve these results with almost any camera that has a B
setting on the shutter, or can select long shutter speeds.  You need
to expose for whole seconds - the more seconds the better, depending
on what effect you want to create.

Above all, you need a sturdy tripod to keep the camera absolutely
still.  You will also need a cable release to fire the shutter without
jerking the camera.

A digital camera would be best so you can see the results as you go,
learn from them and make adjustments to your technique.  You will need
a camera that is capable of having the exposure (aperture and shutter
speed) selected manually.

It is all possible with film but the lack of instant feedback makes it
far more difficult than with digital.

b> Hi everyone,
b>
b>   I've come across many beautiful pictures of roads/flyovers captured
b> at night, which show colorful streaks of the head/tail lamps of
b> vehicles running on them. Surely, these are results of special trick-
b> photography and not mere digital effects on a computer.
b>
b>   Could you please elaborate on what camera is required for capturing
b> such images, and what care is to be taken. I hope a small aperture and
b> long exposure would help, but are there issues with the type of film/
b> ccd? Please comment.
b>

There is going to be a tradeoff between length of streak and exposure of
background.  This one for example (a snapshot through a dirty window!) is
at 4 seconds and at about the largest aperture (smallest f number), f 3.2,
for the camera, at iso 100.
   
http://www.clifford.ac/photo/2005/China.October/Beijing/tn/pb042377.jpg.index.html

The background is not exposed enough.  A longer exposure time would give
longer streaks. I could have upped the iso but that would have more grain.

There is another variable.  This one is taken from the same spot but at
the telephoto end of the zoom. 2 seconds, f3.5, iso 100.  Shorter exposure
because more of the photgraph is light.

http://www.clifford.ac/photo/2005/China.October/Beijing/tn/pb042379.jpg.index.html

The answer I think, is to take some time to experiment with the three
variables of exposure time, iso and aperture, and take lots of photographs
of the scene you are trying to capture. Not what I did - quick snapshots
through a dirty window on automatic mode.

b> Hi everyone,
b>
b>   I've come across many beautiful pictures of roads/flyovers captured
b> at night, which show colorful streaks of the head/tail lamps of
b> vehicles running on them. Surely, these are results of special trick-
b> photography and not mere digital effects on a computer.
b>

Another effect you might find interesting in, in regard to streaks, is the
use of first or second curtain slow synch flash.  Have a look here:  
http://www.megapixel.net/html/articles/article-fmodes.php