Dark matter is a vital component of the current best model of our universe, Lambda-CDM. There are leading candidates for what the dark matter could be (e.g. weakly-interacting massive particles, or axions), but no compelling observational or experimental evidence exists to support these particular candidates, nor any beyond-the-Standard-Model physics that might produce such candidates. This suggests that other dark matter candidates, including ones that might arise in the Standard Model, should receive increased attention. I will discuss the general class of dark matter candidates with characteristic masses and interaction cross-sections characterized in units of grams and square centimeters, respectively — we refer to these macroscopic candidates as Macros. Such dark matter objects could potentially be assembled out of Standard Model particles (quarks and leptons) in the early universe. I will discuss the earth-based, astrophysical, and cosmological observations used to constrain part of the Macro parameter space. Large regions remain unconstrained, however, most notably for nuclear-dense objects with masses in the range between about 50 – 10^17 and 10^20 – 10^24 grams.