user1307: I think this used to be the blk0001.dat file, but it seems that the block chain is now (since version ?) moved to the blocks/ folder, containing a lot of blk* files, as well as an index file and multiple rev* files.
What files do I have to copy to a new machine if I want it to be synced up?
I know I will have to run with -rescan the first time after I changed the block chain files. And I know that the blocks are not verified (but they come from another machine I own, so there are no trust issues).
Please mention the current version number in your answer to not confuse people if the file configuration would change over time.

user6901: https://en.bitcoin.it/wiki/Data_directory
This might be of some help.I followed that and successfully moved the files from C:\Users[username]\AppData\Roaming\Bitcoin\ to E:\BitcoinData.
Just cut and paste the whole content of from the Bitcoin folder (C:\Users[username]\AppData\Roaming\Bitcoin) and set the new target as 
"C:\Program Files (x86)\Bitcoin\bitcoin-qt.exe" -datadir=d:\BitCoinData and that is assuming you have bitcoin Qt installed in your C: drive.Change the path accordingly.

1307: <p>I think this used to be the <code>blk0001.dat</code> file, but it seems that the block chain is now (since version ?) moved to the <code>blocks/</code> folder, containing a lot of <code>blk*</code> files, as well as an <code>index</code> file and multiple <code>rev*</code> files.</p>

<p>What files do I have to copy to a new machine if I want it to be synced up?</p>

<p>I know I will have to run with <code>-rescan</code> the first time after I changed the block chain files. And I know that the blocks are not verified (but they come from another machine I own, so there are no trust issues).</p>

<p>Please mention the current version number in your answer to not confuse people if the file configuration would change over time.</p>
 6901: <p><a href="https://en.bitcoin.it/wiki/Data_directory" rel="nofollow">https://en.bitcoin.it/wiki/Data_directory</a></p>

<p>This might be of some help.I followed that and successfully moved the files from C:\Users[username]\AppData\Roaming\Bitcoin\ to E:\BitcoinData.</p>

<p>Just cut and paste the whole content of from the Bitcoin folder (C:\Users[username]\AppData\Roaming\Bitcoin) and set the new target as </p>

<p>"C:\Program Files (x86)\Bitcoin\bitcoin-qt.exe" -datadir=d:\BitCoinData and that is assuming you have bitcoin Qt installed in your C: drive.Change the path accordingly.</p>
