  In this letter we report on the discovery of a z=2.83 Lyman-alpha Blob (LAB)
found in our wide field narrow-band survey within the Spitzer First Look Survey
region. The blob is extended over at least 95kpc and has a total Lyman-alpha
luminosity of 2.1 x 10^44 erg/s. It is only the sixth LAB known of this scale
(> 50 kpc), and is associated with an embedded continuum source in g', R, i', K
& 4.5 um bands. The LAB's optical spectrum shows clumpy structures and
tantalising hints of a sharp red cut-off and shear within the Ly-alpha emission
line. Studies of the LAB's surface brightness profile and of the continuum
counterpart's spectral energy distribution (SED) indicate that the profuse
Lyman-alpha emission is consistent with being powered by cold gas accreting
onto a massive dark matter halo.
