Yes IRCTC can send a PDF file when the ticket is booked.
Its sad that they dont do that probably because of the amount of server resources that may consume.
However following some simple tips can help
1 . You can make a screenshot of your booking confirmation screen using the print-screen key and then later paste it to paint and save it as jpg and attach to your email so that you will no more be in the mercy of irctc.
2. You can do the same with the "PRINT ETICKET" output screen
3. You can install BULLZIP or similar PDF printer software and make a PDF of the ticket. This is the one I usually use.
4. You can go without a printout at all ! Yes, there is this rule. All you need to carry is your photo ID and you will be charged around Rs50/- extra. I have done this twice.
So no more worry about not able to take printout of irctc etickets. The problem is resolved :)