TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The cold filter plugging point of the composition is below 0 degrees C, preferably -40 degrees C. Preferred Components: The alpha -olefin comprises a 3-12C alpha -olefin, 4-12C alpha -olefin, 5-10C alpha -olefin or their mixture, preferably 1-octene or 1-hexene. The presence of the wax nucleator lowers a cold filter plugging point of the fuel by at least 20 degrees C. The cold filter plugging point of the liquid hydrocarbon is lowered. The liquid hydrocarbon comprises a fuel. Preferred Method: The method further comprises: mixing the liquid hydrocarbon to dissolve the olefin block copolymer; and heating the liquid hydrocarbon to dissolve the olefin block copolymer. The olefin block copolymer is chosen to provide a cold filter plugging point below the lowest expected ambient temperature at which the fuel will be stored, transported, or used.    TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The olefin block copolymer comprises: two or more blocks having different compositions; alternating segments of different levels of crystallinity; one or more blocks comprising at least 75%, preferably at least 95% ethylene units and one or more blocks comprising an ethylene/ alpha -olefin copolymer of different composition; and one or more blocks comprising essentially pure polyethylene and one or more blocks of an ethylene/alpha olefin copolymer of different composition. The number average molecular weight of the olefin block copolymer is 1000-5000000, preferably 20000-250000 g/mole. The olefin block copolymer is: a multiblock copolymer comprising 2-200 blocks; or a block copolymer of polyethylene and poly(ethylene co 1-octene). The wax crystal nucleator is Infuse (RTM: Olefin block copolymer). The wax crystal nucleator is present in an amount of less than 0.1 wt.%, preferably less than 0.0001 wt.% of the fuel composition. The olefin block copolymer contains: no residual sites of unsaturation; and no residue or side-products resulting from catalytic hydrogenation. The olefin block copolymer has a structure of formula (-(-A-)a-(-B1-A-)-(-B1-)c).A = -(-(-C(R1a)-CH2)x-(-CH2-CH2-)1-x-)n-;B1 = -(-(-C(R1b)-CH2)y-(-CH2-CH2-)1-y-)m-;R1a, R1b = 1-10C alkyl, preferably ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl or n-decyl;a, c = 0 or 1;b = 1-100;x = 0-1;y = 1/1000-1; andm, n = 5-5000, where at least one of (R1a and R1b) or (x and y) are different, and a ratio between n and m is 0.01-100, 0.1-1, 1-10 or 10-100. EXAMPLE - None given.