Hai.
I couldn't find any tool for the site to download pages or pools at once, so i made my own software.
At the moment you can only download Pages, pools will come soon.
Known bugs:
If it says 0 Images try a higher Pages count.
Screenshots:
http://prntscr.com/3zs18q
http://prntscr.com/3zs1dt
And at least the Download:
http://software.cryptic-revolution.de/E621-DownloadManager.exe
Updated by Ritual Catharsis