Demeter Compulator compressor pedal
I did a bit of digging around on various forums for bass guitarists looking for a well regarded but affordable compressor, and the Compulator seemed to fit the bill. It's exactly what I wanted, since it does the job without altering my tone and I only really notice what it does when I turn it off.
Darkglass B3K distortion pedal
Although it's referred to as an overdrive pedal for bass guitar, it's actually more of a distortion pedal. The tone doesn't have the "fuzziness" and sustain of an overdrive, and it's great for harsh, gated distortion sounds. Think of it as the sound of Lemmy from Motorhead in a small black box, as that's the kind of thing this pedal is capable of.
Electro Harmonix Stereo Clone Theory
EH specialise in effect pedals that are a bit more in your face than the typical alternatives. The Clone Theory provides a distinctively metallic chorus sound that's particularly well suited to bass guitar. Check out the bass guitar sound of Peter Hook, as the older version of the Clone Theory is what that he uses to get his trademark tone.
MXR Phase 100
A classic pedal that was used by Gary Numan to get the distinctive swirling keyboard sounds on songs like Cars.
MXR 10 Band Equaliser
Another classic pedal that has been in production since the 1970s and was used by Joy Division.
Dynacord EC-280 Echo
This was the first echo unit from Dynacord that didn't rely on a tape loop. It's a BBD with settings for reverb as well as delay. The chorus control is also capable of producing flanged sounds.
Melos Tape Echo
A simple tape loop based echo from Japan that uses a cartridge that was originally intended for answer phones. One of these was used extensively by legendary producer Martin Hannett.
Melos DE-1 Echo
A BBD based echo that was also a favourite of Martin Hannett.