diff --git a/Makefile.am b/Makefile.am
index cb8256fe..891e72de 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -157,7 +157,7 @@ shaders_DATA = src/video/Basic.vsh src/video/Basic.fsh
 disksdir = @datadir@/@PACKAGE@/disks
 disks_DATA = \
 	disks/README disks/blank.dsk.gz disks/blank.nib.gz disks/blank.po.gz disks/etc.dsk.gz \
-	disks/mystery.dsk disks/speedtest.dsk disks/speedtest.txt disks/flapple140.po \
+	disks/mystery.dsk.gz disks/speedtest.dsk.gz disks/speedtest.txt disks/flapple140.po.gz \
 	disks/testdisplay1.dsk.gz disks/testdisplay1.nib.gz disks/testvm1.dsk.gz disks/testvm1.nib.gz
 
 
diff --git a/disks/NSCT.dsk b/disks/NSCT.dsk
deleted file mode 100644
index fd932d92..00000000
Binary files a/disks/NSCT.dsk and /dev/null differ
diff --git a/disks/NSCT.dsk.gz b/disks/NSCT.dsk.gz
new file mode 100644
index 00000000..0e173339
Binary files /dev/null and b/disks/NSCT.dsk.gz differ
diff --git a/disks/flapple140.po b/disks/flapple140.po
deleted file mode 100644
index 2231c298..00000000
Binary files a/disks/flapple140.po and /dev/null differ
diff --git a/disks/flapple140.po.gz b/disks/flapple140.po.gz
new file mode 100644
index 00000000..41f8d031
Binary files /dev/null and b/disks/flapple140.po.gz differ
diff --git a/disks/mystery.dsk b/disks/mystery.dsk
deleted file mode 100644
index 637e7ec3..00000000
Binary files a/disks/mystery.dsk and /dev/null differ
diff --git a/disks/mystery.dsk.gz b/disks/mystery.dsk.gz
new file mode 100644
index 00000000..a44e64cf
Binary files /dev/null and b/disks/mystery.dsk.gz differ
diff --git a/disks/speedtest.dsk b/disks/speedtest.dsk
deleted file mode 100644
index c10dd95c..00000000
Binary files a/disks/speedtest.dsk and /dev/null differ
diff --git a/disks/speedtest.dsk.gz b/disks/speedtest.dsk.gz
new file mode 100644
index 00000000..5b7c35d6
Binary files /dev/null and b/disks/speedtest.dsk.gz differ
diff --git a/disks/testvm1.dsk b/disks/testvm1.dsk
deleted file mode 100644
index 8ca7fbd1..00000000
Binary files a/disks/testvm1.dsk and /dev/null differ