Twin directories of acrobot:

[DIR]  ftp://ftp.digitaltrust.it/ftp/savannah/files/acrobot/
[DIR]  ftp://ftp.uni-mainz.de/pub/software/gnu/savannah/files/acrobot/
[DIR]  ftp://sapi.vlsm.org/gnuftp/savannah/files/acrobot/
[DIR]  ftp://147.52.159.12/mirrors/nongnu.org/acrobot/
[DIR]  ftp://200.17.202.1/savannah-nongnu/acrobot/
[DIR]  ftp://200.17.202.16/savannah-nongnu/acrobot/
[DIR]  ftp://200.17.202.17/savannah-nongnu/acrobot/
[DIR]  ftp://ftp.kreonet.re.kr/gnu/ibiblio/www/savannah-checkouts/non-gnu/acrobot/
[DIR]  ftp://ftp.gwdg.de/pub/gnu/www/savannah-checkouts/non-gnu/acrobot/