That depends on 2 things: which project is involved, and which client you are using (UD or BOINC).

For any combination of the above, the files transferred are very small. Less than a megabyte, sometimes much less.

Remember, though, the first time you connect the client will download the science application (which is also fairly small).

On broadband, you won't even notice the downloads. On dialup, it is perfectly reasonable.

Depending on Rosetta or FAAH, in BOINC you can actually witness it in the Transfer Tab. Most seem to be in the area of <1mb, sometimes though 3.5 to 4mb a piece. It's all a function of the size of the chunck. I've not correllated it to the time crunched aspect....that may play a role.

PS, come to think, i remember UD has a little transfer ticker right hand bottom when sending results and fething work.

Have a nice day.