Package list broken

I've broken something while taking a look at Pinguy. I followed the troubleshooting hints from Launchpad (great resource by the way!) and got the following:

simon@simon-Studio-XPS-1640:~$ sudo fuser -vvv /var/lib/dpkg/lock
[sudo] password for simon:
simon@simon-Studio-XPS-1640:~$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=11.04
DISTRIB_CODENAME=natty
DISTRIB_DESCRIPTION="Ubuntu 11.04"
simon@simon-Studio-XPS-1640:~$ uname -a
Linux simon-Studio-XPS-1640 2.6.38-9-generic #43-Ubuntu SMP Thu Apr 28 15:25:15 UTC 2011 i686 i686 i386 GNU/Linux
simon@simon-Studio-XPS-1640:~$ sudo rm /var/lib/apt/lists/lock
rm: cannot remove `/var/lib/apt/lists/lock': No such file or directory
simon@simon-Studio-XPS-1640:~$ sudo cp -arf /var/lib/dpkg /var/lib/dpkg.backup
simon@simon-Studio-XPS-1640:~$ sudo cp /var/lib/dpkg/status-old /var/lib/dpkg/status
simon@simon-Studio-XPS-1640:~$ sudo cp /var/lib/dpkg/available-old /var/lib/dpkg/available
simon@simon-Studio-XPS-1640:~$ sudo rm -rf /var/lib/dpkg/updates/*
simon@simon-Studio-XPS-1640:~$ sudo rm -rf /var/lib/apt/lists
simon@simon-Studio-XPS-1640:~$ sudo rm /var/cache/apt/*.bin
simon@simon-Studio-XPS-1640:~$ sudo mkdir /var/lib/apt/lists
simon@simon-Studio-XPS-1640:~$ sudo mkdir /var/lib/apt/lists/partial
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get clean
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get autoclean
Reading package lists... Error!
E: Malformed line 1 in source list /etc/apt/sources.list.d/apticons.list (dist parse)
E: The list of sources could not be read.
E: The package lists or status file could not be parsed or opened.
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get --purge autoremove
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get update -o APT::Cache-Limit=25165824
E: Malformed line 1 in source list /etc/apt/sources.list.d/apticons.list (dist parse)
E: The list of sources could not be read.
simon@simon-Studio-XPS-1640:~$ sudo dpkg --clear-avail
simon@simon-Studio-XPS-1640:~$ sudo dpkg --configure -a
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get -f install
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get --fix-missing install
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
simon@simon-Studio-XPS-1640:~$ LANG=C;sudo apt-get update -o APT::Cache-Limit=25165824 && sudo apt-get dist-upgrade
E: Malformed line 1 in source list /etc/apt/sources.list.d/apticons.list (dist parse)
E: The list of sources could not be read.

There seems to be nothing wrong in my sources.list.
The contents of /etc/apt/sources.list.d/apticons.list is only the following line:
deb http://dl.dropbox.com/u/7948220/eve/ubuntu-natty natty

and the following in ...apticons.list.save
deb http://dl.dropbox.com/u/7948220/eve/ubuntu-natty unstable/

How do I get back to normal? Thanks for reading!