cat linux.words extra.words | sort | uniq | perl -lne "$_ = lc; tr/olzs/0125/; (length == 4 or length == 8) and /^[0-9a-f]+$/ and print"

abba
abbe
abed
abe1
ab1e
ab05
acce55ed
acce55e5
acc01ade
ace5
add5
a1a5
a1ba
a1ec
a1ee
a1fa
a10e
a150
a55e55ed
a55e55e5
babe
bade
ba1d
ba1e
ba11
ba5e
ba5eba11
ba5e1e55
ba55
bead
beda221e
bed5
beef
bee5
be1a
be11
be55
b1ab
b1ed
b10b
b10c
b0b5
b0ca
b0de
b01d
b01dface
b011
b00b
b005
b05e
b055
cab5
cafe
ca1f
ca11
ca11ab1e
ca5caded
ca5cade5
ca5e
cede
ce11
c1ad
c10d
c0a1
c0a1e5ce
c0bb
c0ca
c0c0
c0de
c0ed
c01d
c01e
c01055a1
c001
dada
dade
dad5
da1e
da2e
dead
deaf
dea1
decea5ed
decea5e5
deed
de11
d0dd
d0e5
d01e
d011
d05e
d02e
ea5e
ebb5
ee15
e1ba
e11a
e15e
face
fade
fa11
fa2e
feed
fee1
fee5
fe11
fe55
f1ea
f1ed
f1ee
f0a1
f0e5
f01d
f00d
f001
f055
1abe11ed
1ab5
1ace
1ad5
1a05
1a55
1ead
1eaf
1eaf1e55
1ee5
1e55
10ad
10af
10be
10eb
101a
105e
1055
0b0e
0dd5
0de5
0ff5
01af
002e
0510
5afe
5a1e
5a12
5cab
5caff01d
5ca1ab1e
5ea1
5ea5
5eed
5ee5
5e1f
5e11
51ab
51ed
510b
50b5
50da
50d5
50fa
501d
501e
5010
2ea1
2005

Take out the length restriction to get a much longer list, but 4 and 8 are valid for 16- and 32-bit integers.

Get rid of the tr/olz/012/ if you really want a short list, although its cool because it spells "trolls".

It's also weird that we get c0ca, but no c01a.

Of course, you can combine the short words. Some of the classics (you should know where you've seen these before) are of this type:

cafebabe
deadbeef