0101010101010101 fefefefefefefefe 1f1f1f1f1f1f1f1f e0e0e0e0e0e0e0e0
The following keys are semi-weak keys for DES and should be avoided:
01fe01fe01fe01fe fe01fe01fe01fe01 1fe01fe01fe01fe0 e01fe01fe01fe01f 01e001e001e001e0 e001e001e001e001 1ffe1ffe1ffe1ffe fe1ffe1ffe1ffe1f 011f011f011f011f 1f011f011f011f01 e0fee0fee0fee0fe fee0fee0fee0fee0
The following keys are possibly weak keys for DES and should be avoided:
1f1f01010e0e0101 e00101e0f10101f1
011f1f01010e0e01 fe1f01e0fe0e01f1
1f01011f0e01010e fe011fe0fe010ef1
01011f1f01010e0e e01f1fe0f10e0ef1
fe0101fefe0101fe
e0e00101f1f10101 e01f01fef10e01fe
fefe0101fefe0101 e0011ffef1010efe
fee01f01fef10e01 fe1f1ffefe0e0efe
e0fe1f01f1fe0e01
fee0011ffef1010e 1ffe01e00efe01f1
e0fe011ff1fe010e 01fe1fe001fe0ef1
e0e01f1ff1f10e0e 1fe001fe0ef101fe
fefe1f1ffefe0e0e 01e01ffe01f10efe
fe1fe001fe0ef101 0101e0e00101f1f1
e01ffe01f10efe01 1f1fe0e00e0ef1f1
fe01e01ffe01f10e 1f01fee00e0ef1f1
e001fe1ff101fe0e 011ffee0010efef1
1f01e0fe0e01f1fe
01e0e00101e1e101 011fe0fe010ef1fe
1ffee0010efef001 0101fefe0101fefe
1ffee0010ef1fe01 1f1ffefe0e0efefe
01fefe0101fefe01
1fe0e0f10ef1f10e fefee0e0fefef1f1
01fee01f01fef10e e0fefee0f1fefef1
01e0fe1f01f1fe0e fee0e0fefef1f1fe
1ffefe1f0efefe0e e0e0fefef1f1fefe
There are quite likely typos in this list; it is taken from Bruce Schneier's Applied Cryptography (first ed, p. 235, if you want to double-check).
You can always generate the list yourself; the weak keys are keys that, after striping out the parity bit and doing the first permutation, split into two halves with each half either all 0's or all 1's.
The semi-weak keys are keys that, when you use them to generate the 16 subkeys, generate only two different subkeys instead of 16 different ones.
The possibly weak keys are keys that generate only 4 different subkeys of 16.