Microlitre polymer droplets deposit solid conical structures, via a novel bootstrap drying mechanism, over a range of initial conditions. Accepted for publication in Phys. Chem.Chem.Phys, 2010, DOI: 10.1039 Abstract Sessile droplets of aqueous poly(ethylene oxide) solution, with average molecular weight of 100kDa, are monitored during evporative drying at ambient conditions over a range of initial concentrations c 0 . For all droplets with c 0 ≥ 3%, central conical structures, which can be hollow and nearly 50% taller than the initial droplet, are formed during a growth stage. Although the formation of superficially similar structures has been explained for glass-forming polymers using a skin-buckling model which predicts the droplet to have constant surface area during the growth stage (L.Pauchard and C. Allain, Europhys. Lett., 2003, 62, 897-903), we demonstrate that this model is not applicable here as the surface area is shown to increase during growth for all c 0 . We interpret our experimental data using a proposed drying and deposition process comprising the four stages: pinned drying; receding contact line; "bootstrap" growth, during which the liquid droplet is lifted upon freshly-precipitated solid; and late drying. Additional predictions of our model, including a criterion for predicting whether a conical structure will form, compare favourably with observations. We discuss how the specific chemical and physical properties of PEO, in particular its amphiphilic nature, its tendency to form crystalline spherulites rather than an amorphous glass at high concentrations and its anomalous surface tension values for M W = 100 kDa may be critical to the observed drying process.