Twin directories of .a:

[DIR]  ftp://ftp.cs.wits.ac.za/uploads/.a/
[DIR]  ftp://ftp.nectec.or.th/.a/
[DIR]  ftp://ftp.cs.fiu.edu/pub/flynnj/.a/
[DIR]  ftp://ftp.funet.fi/pub/OS/incoming/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Canada/diesel/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/misc/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Canada/British_Columbia_Railway/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/DMU/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/EMU/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/carriages/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/diesel/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/electric/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Finland/steam/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Sweden/X2000/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Sweden/diesel/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Sweden/electric/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Sweden/misc/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/United_States/Boston-Maine/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Germany/electric/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Australia/DMU/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Australia/EMU/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Australia/carriage/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Australia/diesel/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Australia/tram/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Australia/zigzag/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Denmark/DMU/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Denmark/diesel/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Germany/EMU/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Germany/steam/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Germany/trams/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Portugal/trams/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/Switzerland/electric/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/United_States/BNSF/.a/
[DIR]  ftp://ftp.funet.fi/pub/pics/railways/United_States/Trolley/.a/
[DIR]  ftp://ftp.research.telcordia.com/pub/nmh/.a/