lipid droplets
Lipid droplets form the main lipid store in eukaryotic cells. Although all cells seem to be able to generate lipid droplets, their biogenesis, regulatory mechanisms and interactions with other organelles remain largely elusive.
References
Martin S, Parton RG. Lipid droplets: a unified view of a dynamic organelle. Nat Rev Mol Cell Biol. 2006 May;7(5):373-8. PMID: 16550215