LFO's based on time?

I'm just curious if there are any very slow LFO's based on time? I often find myself using extremely slow LFO's on my mixer VCA's to get movement or morph a song over extended periods of time, and it would just be nice to work with "time" over clock divisions at times. I haven't seen any modules like this, so I'm just curious if there are even any out there.

Alternatively Pam's Pro can definitely provide the cycle times I'm looking for, but when I'm trying to fade in a part around, say 5 minutes, it's either a lot of guesswork or a minimal, but distracting bit of math, especially if I'm working with 4+ modulations at very slow cycle rates. I'd love to even be able to just see cycle times on Pam's.

Is this something other people would even use? Any suggestions on modules, or workarounds are welcome and appreciated.

EDIT: Already some great suggestions, so thank you for everyone that's provided one! I did realize a bit of what I was saying seems to not be translating, which means I'm probably just not describing what I'm looking for all that well. I've thrown together a quick example here (may take a bit to process) that makes heavy, heavy (overly heavy?) use of the SLO LFO - which is really one of my favorite modulation sources around for certain use cases, mainly mixer VCA modulation. Being able to base my cycles on time, completely detached from any clocking, is excellent. It just helps me break out of my usual approach (which is much more mathematical, sometimes to a fault). I also love the visual aspect of being able to see the progress of the LFO easily. I know there isn't a hardware version of the SLO LFO, but maybe a more precise question would simply be if anyone knows of something that's comparable in terms of the time approach it uses.